Latency-based master bud role swap

Abstract

Aspects describe methods for improving primary earbud handover decisions. Audio dropouts can be reduced by incorporating an audio latency variability metric into the handover decision algorithm. In aspects, a predicted audio latency variability metric is used in combination with signal quality measurements to determine when to hand over the role of primary earbud between earbuds in an earbud system.

Description

[Technical Field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. patent application Ser. No. 18 / 152,565, filed Jan. 10, 2023, the contents of which are incorporated herein by reference in their entirety as if fully set forth below.

[0002] Aspects of the present disclosure describe an earbud system, in which each earbud in the system is in wireless communication with the other earbuds and can selectively receive streams of audio data from a user device. A primary or master earbud in the earbud system requests specific audio data packets from the user device and transmits the audio data to secondary earbuds in the earbud system. Aspects describe methods performed by the earbud system for handing over the role of primary earbud between earbuds in the system based at least in part on audio latency variance of the audio streams. [Background technology]

[0003] Wireless earbuds advantageously eliminate the hassle of adjusting wires and tethers to user devices, thereby allowing users to enjoy wireless listening in a variety of situations. For example, wireless earbuds are suitable for voice calls, gaming, listening to music while exercising, and watching movies. They offer flexibility for active lifestyles with robust audio output. The user experience can be improved by avoiding unnecessary audio dropouts, especially during travel. Summary of the Invention

[0004] Aspects provide methods and earbud systems that perform methods for handing over primary earbud roles based at least in part on audio latency variability.

[0005] In one aspect, an earbud system is provided. The earbud system includes a first earbud (right earbud) and a second earbud (left earbud). When the right earbud serves as the primary earbud of the earbud system, the right earbud wirelessly receives audio data from a user device, requests specific audio data packets from the user device, and wirelessly communicates with the left earbud, which serves as the secondary earbud of the earbud system. The right earbud performs a procedure to hand over the role of the primary earbud to the left earbud based at least in part on an audio latency variance of the audio data.

[0006] In aspects, the audio latency of the audio data received by the right earbud is a proxy for the volatility of the buffered audio in the right earbud.

[0007] In an aspect, the procedure includes determining an acceptable signal quality between the user device and the right earbud; determining an acceptable signal quality between the user device and the left earbud; assuming that an audio latency variance of audio data at the left earbud is acceptable based at least in part on the acceptable signal quality between the user device and the left earbud; calculating, by the right earbud, that an audio latency variance of the audio data received by the right earbud exceeds a threshold when the audio latency variance of the audio data at the left earbud is acceptable; and handing over the role of the primary earbud to the left earbud based on the calculation, such that the left earbud functions as the primary earbud and the right earbud functions as the secondary earbud.

[0008] In an aspect, the procedure further includes calculating, by the left earbud, that an audio latency variance of audio data received by the left earbud acting as the primary earbud from the user device is unacceptable, and handing over the role of the primary earbud to the right earbud based on the calculated unacceptable audio latency variance of the audio data received by the left earbud.

[0009] In an aspect, the signal quality comprises at least one of a link quality indicator (LQI) or a received signal strength indicator (RSSI).

[0010] In aspects, an earbud of an earbud system performing the role of a primary earbud calculates an audio latency variance associated with the primary earbud based on audio data received from the user device.

[0011] In aspects, an earbud of an earbud system functioning as a secondary earbud estimates an audio latency variance associated with the secondary earbud based at least in part on the signal quality between the secondary earbud and the user device.

[0012] An aspect provides a method performed by an earbud system, comprising: wirelessly receiving audio data from a user device at a right earbud when acting as a primary earbud for the earbud system; and performing, by the earbud system, a procedure for handing over the role of the primary earbud to a left earbud of the earbud system based on an audio latency variance of the audio data received by the right earbud.

[0013] In an aspect, performing the procedure includes determining an acceptable signal quality between the user device and the right earbud; determining an acceptable signal quality between the user device and the left earbud; assuming that an audio latency variance of audio data at the left earbud is acceptable based at least in part on the acceptable signal quality between the user device and the left earbud; calculating, by the right earbud, that an audio latency variance of audio data received by the right earbud exceeds a threshold when the audio latency variance of the audio data at the left earbud is acceptable; and handing over the role of the primary earbud to the left earbud based on the calculation, such that the left earbud functions as the primary earbud and the right earbud functions as the secondary earbud.

[0014] In an aspect, the procedure further includes calculating, by the left earbud, that an audio latency variance of audio data received by the left earbud acting as the primary earbud from the user device is unacceptable, and handing over the role of the primary earbud to the right earbud based on the calculated unacceptable audio latency variance of the audio data received by the left earbud.

[0015] In an aspect, the signal quality comprises at least one of a link quality indicator (LQI) or a received signal strength indicator (RSSI).

[0016] In an aspect, determining the acceptable signal quality between the user device and the right earbud includes determining an acceptable link quality indicator and an acceptable received signal strength indicator, and determining the acceptable signal quality between the user device and the left earbud includes determining an acceptable link quality indicator and an acceptable received signal strength indicator.

[0017] In an aspect, the method further includes calculating, by the earbud of the earbud system performing the role of the primary earbud, an audio latency variance associated with the primary earbud based on the audio data received from the user device.

[0018] In an aspect, the method further includes estimating, by an earbud of the earbud system functioning as the secondary earbud, an audio latency variance associated with the secondary earbud based at least in part on a signal quality between the secondary earbud and the user device. In an aspect, performing the handover is further based at least in part on a comparison between the calculated audio latency variance and the estimated audio latency variance.

[0019] In an aspect, the method further includes determining an acceptable signal quality between the user device and the right earbud and an acceptable signal quality between the user device and the left earbud, and the handover procedure is performed based on the acceptable signal quality between the user device and the right earbud, the acceptable signal quality between the user device and the left earbud, and an audio latency variance of the audio data received by the right earbud.

[0020] An aspect provides a method performed by an earbud system, when acting as a primary earbud for the earbud system, including: wirelessly receiving audio data at a right earbud from a user device; determining that each of a link quality indicator (LQI) and a received signal strength indicator (RSSI) of the audio data from the user device to the right earbud are acceptable; determining that each of the LQI and RSSI of the audio data are acceptable at a left earbud of the earbud system; determining that an audio latency variance of the audio data at the right earbud will be unacceptable; and performing, by the earbud system, a procedure to hand over the role of primary earbud to the left earbud of the earbud system based on the acceptable LQI and RSSI at the right earbud, the acceptable LQI and RSSI at the left earbud, and the unacceptable audio latency variance of the audio data received by the right earbud.

[0021] In an aspect, the method further includes determining, after the procedure, that an audio latency variance of the audio data in the left earbud acting as the primary earbud becomes unacceptable, determining that a handover condition is met, and performing, by the earbud system, a procedure to hand over the role of the primary earbud to the right earbud based on the audio latency variance of the audio data in the left earbud becoming unacceptable and the handover condition being met.

[0022] In an aspect, the handover conditions include the right earbud being the preferred dominant earbud of the earbud system.

[0023] In an aspect, the handover condition includes determining that at least one of the LQI or RSSI in the right earbud has improved.

[0024] In aspects, the audio latency of the audio data received by the right earbud is a volatile proxy for the audio buffered in the right earbud.

[0025] All examples and features mentioned in this specification can be combined in any technically possible manner. Other features, objects, and advantages will become apparent from the following detailed description when read in conjunction with the following drawings. [Brief explanation of the drawings]

[0026] [Figure 1] 1 illustrates an exemplary system including an earbud system and a user device. [Figure 2] 1 illustrates an exemplary method performed by an earbud system according to an aspect of the present disclosure. [Figure 3] 1 illustrates a prioritization of metrics used to determine whether handover conditions are met. [Figure 4] An exemplary transformation of each metric that results in a "pass" or "fail" indication is shown. [Figure 5] 1 illustrates an exemplary try-and-see approach that uses the LAT to determine when to hand over the role of the primary earbud to the secondary earbud. [Figure 6] 1 illustrates an example handover procedure according to an aspect of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0027] Wireless audio output devices have become a common and convenient part of everyday life. A truly wireless audio output device offers the benefits of an audio device with the added convenience of being completely free of any cables or connectors linking both earbuds together or to a user device.

[0028] 1 illustrates an exemplary system 100 according to an embodiment of the present disclosure. The earbud system consists of two earbuds: a right earbud 102a (sometimes referred to as bud A) and a left earbud 102b (sometimes referred to as bud B). Both the right earbud 102a and the left earbud 102b can wirelessly communicate with a user device 104, which streams audio data to the earbud system.

[0029] In an exemplary scenario, the earbud system is a true wireless system. One of the earbuds, designated as the primary earbud (master or primary receiver), receives audio data wirelessly from the user device. The primary earbud also controls requests for specific packets of audio data from the user device. The other earbud is the secondary earbud (secondary receiver). The secondary earbud receives its audio data from the primary earbud by eavesdropping on traffic between the primary earbud and the user device.

[0030] 1, the right earbud 102a is the primary earbud because it controls the request for packets from the user device 104. In one aspect, the primary earbud receives audio data via Bluetooth signals, however, any wireless protocol may be used. The secondary earbud 102b receives the audio data by eavesdropping on the primary earbud 102a's connection with the user device 104 and requesting the primary earbud 102a to send any missing audio packets to the secondary earbud 102b.

[0031] Although not shown, each earbud includes a transmitter, a receiver, an audio data buffer, a wireless communication protocol stack (e.g., a Bluetooth stack), and circuitry configured to control the functionality of the earbud. The user device may be any device that communicates with the earbuds and streams audio data to the earbuds. The terms "right earbud" and "left earbud" are used for illustrative purposes only, and it is assumed that the earbud system includes two earbuds, referred to herein as a right earbud and a left earbud, and that each earbud can assume the role of a primary earbud.

[0032] As mentioned above, the primary earbud is responsible for connecting with the user device. The primary earbud performs several roles, including acting as a bridge between the audio source user device and the secondary earbud, managing the audio connection between the two earbuds, and, in aspects, compensating for audio delays that may occur between the earbuds during transmission. Therefore, selecting a primary earbud and handing over the role of primary earbud to another earbud when appropriate is important to avoid unnecessary audio dropouts. Therefore, an improved method for determining when to switch the role of primary earbud between earbuds in an earbud system is desirable.

[0033] Currently, handover decisions are based on the signal quality between the user device and each of the earbuds. Two indicators of signal quality for an audio signal are the link quality indicator (LQI) and the received signal strength indicator (RSSI). The LQI is calculated by the underlying Bluetooth stack in each of the respective earbuds. Based on the Bluetooth Core Specification, each Bluetooth module provides a measurement of link quality. The measurement is based on signal strength over time and packet fragmentation measurements. The RSSI is the measured received signal strength in dB of the signal to the connected earbud. Similar to the LQI, each earbud measures its respective RSSI. In aspects, each earbud communicates its LQI and RSSI to other earbuds in the system.

[0034] Signal quality between a user device and a connected earbud system focuses on general conditions and measurements of current events. To more accurately determine which earbud is better suited to function as the primary earbud, aspects of the present disclosure base handover decisions on predictors associated with audio stability trends.

[0035] According to aspects of the present disclosure, a handover decision algorithm implemented by an earbud system uses audio latency variance (LAT) to determine when to switch the role of primary earbud between earbuds in the system. LAT measures the volatility of buffered audio in the earbuds. When the audio buffer becomes depleted, the user experiences audio dropouts. A high LAT may indicate that the primary earbud is not receiving audio data quickly enough, as the buffer fills and empties rather than remaining in a steady state. A high LAT can result in audio dropouts, and therefore it is desirable to avoid a high LAT.

[0036] In a true wireless earbud system, such as that shown in FIG. 1, audio data is continuously streamed from the user device. The primary earbud receives audio data from the user device and controls requesting specific packets of audio data from the user device as needed. The secondary earbud receives the audio by listening to the primary earbud's connection to the user device and requesting any missing packets from the primary earbud. Audio latency is a measurement related to the amount of streaming audio buffered by the earbud system. To ensure smooth playback without dropouts, this buffer cannot be emptied. If the buffer is empty, playback stops until more audio data is received from the user device. For example, it may be desirable to ensure that 150 milliseconds of audio is available in the buffer at any time. A 150-millisecond buffer of audio data means that the system can fail to receive any new audio data from the user device for up to 150 milliseconds before playback must be interrupted. As the buffer is consumed, the audio latency value changes to reflect the time between incoming packets. The volatile trend of the audio latency measurement is used as a predictor of potential audio dropout events and as a predictor of signal quality.

[0037] One way to learn the volatility of a dataset is to calculate the variance. In one aspect, the rolling population variance calculation is derived from Welford's method, which analyzes the difference between two consecutive variance values. Additional filtering in the time domain (an infinite impulse response (IIR) filter, as with other metrics) produces a sufficiently stable measurement. Under ideal conditions, the audio buffer is consistently full, with variance equal to or very close to zero. Conditions that may lead to buffer exhaustion will exhibit statistically higher variance values ​​as the buffer repeatedly fills, depletes, and fills.

[0038] Certain earbud usage patterns result in insufficient or unstable audio buffer depth while regular measurements of LQI and RSSI remain acceptable. In one example, the signal path from the user device to the earbud is not direct, and audio packets have a longer than expected flight time. In another example, there are few or no nearby surfaces that the signal can bounce off of (e.g., when the user is outside), and the "shortest path" signal path involves passing through the user's body.

[0039] In yet another example, signal paths are inconsistent. If some signal paths are significantly "shorter" than others, audio packets may arrive out of order. The audio device then needs to discard and request retransmission, which can lead to buffer exhaustion. One example of some signal paths being "shorter" than others is observed when a user holds a user device in their hands while running. The swing of the user's arms creates very different signal paths as they move up near the head (direct path) and down toward the waist (path through the body). Thus, while conventional methods of using signal strength to determine when to hand over the primary bud role are useful, aspects of the present disclosure use the LAT to influence handover decisions. In aspects, as described in more detail below, the LAT is used in conjunction with signal strength measurements to determine whether handover conditions are met.

[0040] 2 illustrates an exemplary method 200 performed by an earbud system according to an aspect of the present disclosure. At 202, a first earbud (e.g., a right earbud), when acting as the primary earbud of the earbud system, wirelessly receives audio data from a user device, requests specific audio data packets from the user device, and wirelessly communicates with a second earbud (e.g., a left earbud) functioning as the secondary earbud of the earbud system. As shown in FIG. 1, the right earbud may be earbud 102a, the left earbud may be earbud 102b, and the user device may be 104.

[0041] At 204, the right earbud performs a procedure to hand over the role of primary earbud to the left earbud based at least in part on the LAT of the audio data. The audio latency variance provides insight into trends in the stability of the audio stream and helps predict signal loss before it occurs.

[0042] In an aspect, signal quality, which measures current conditions, can be used in combination with LAT, which focuses on predicted audio stability trends, to make handover decisions. In one example, a signal quality score is generated based on LQI, RSSI, and LAT.

[0043] 3 shows a prioritization 300 of metrics used to determine if handover conditions are met. LQI and RSSI measure current signal quality. Therefore, LQI and RSSI have a higher priority than predictive indicators such as LAT. Considering all three metrics together provides a balance that considers general (immediate / emergency) and predictive conditions to more accurately determine when to hand over the primary earbud role.

[0044] Each of the three metrics starts out as a numeric value; however, for the purposes of making handover decisions, only a pass / fail (acceptable / unacceptable) classification is required. To convert each numeric value into a binary rating, each measurement undergoes a series of transformations.

[0045] FIG. 4 shows an example transformation 400 for each metric that results in a "pass" or "fail" indication. At 402, raw measurements are subjected to an IIR filter, resulting in a time-smoothed value. At 404, the time-smoothed value is subjected to hysteresis and thresholding so that the time-smoothed value is evaluated as one of excellent, good, poor, or disastrous. At 406, the evaluation criteria classify the evaluation as either pass (acceptable) or fail (unacceptable). In one example, excellent or good may be evaluated as pass (acceptable), and poor or disastrous may be classified as fail (unacceptable). FIG. 4 shows a high-level transformation that may be applied to each metric. Each metric may have platform-specific filtering constants, hysteresis, and thresholding based on data analysis and tuning.

[0046] In an exemplary method, the scores associated with each metric are arranged in descending order of prevalence / urgency, as shown in FIG. 2. The most common metric is given a higher weighting if the predictive metric fails to predict the correct future state. In one example, an unacceptable LQI in the current primary earbud and an acceptable LQI in the secondary earbud will result in a handover without considering RSSI and LAT. Similarly, if both the primary and secondary earbud have acceptable LQI, and the primary earbud has an unacceptable RSSI and the secondary earbud has an acceptable RSSI, the buds will swap roles without considering LAT.

[0047] In real time (or near real time), both the primary and secondary earbuds can measure their respective LQI and RSSI. Because the primary earbud controls the stream of audio packets from the user device, it can calculate (determine, generate) consistent LAT measurements. Given a true wireless architecture, the secondary earbud eavesdrops on the connection between the primary earbud and the user device. Therefore, the secondary earbud may not be able to measure the LAT. A good or better LQI and RSSI usually implies a healthy audio buffer. Therefore, for the secondary earbud, the LAT assessment is set to acceptable whenever the RSSI and LQI change to good or excellent assessments on the secondary earbud. The secondary earbud may assume an acceptable LAT when the LQI and RSSI are determined to be acceptable.

[0048] 5 shows an example try-and-see technique 500 that uses the LAT to determine when to hand over the role of the primary earbud to the secondary earbud. For illustrative purposes, the primary earbud in this example is initially bud A, and the secondary earbud is initially bud B. The primary (bud A) earbud and secondary (bud B) earbud measure their LQI and RSSI. In an aspect, the primary earbud (bud A) receives the LQI and RSSI calculated by the secondary earbud (bud B). Additionally, the primary earbud (bud A) measures its LAT.

[0049] At 502, it is determined that both the primary earbud (bud A) and the secondary earbud (bud B) have good or better LQI and RSSI ratings. At this point, the handover criteria are not met.

[0050] At 504, the primary earbud (bud A) begins to experience instability in its audio buffer, resulting in an increase in the measured LAT. The LAT assessment for the primary earbud (bud A) is assessed as poor or unacceptable. In one aspect, the LAT is greater than a threshold, meaning that the primary earbud (bud A) is not receiving audio data fast enough.

[0051] At 506, given the good or better LQI and RSSI estimates in the secondary earbud (bud B), the LAT of the secondary earbud (bud B) is assumed to be acceptable.

[0052] Since both earbuds have acceptable LQI and RSSI, the handover conditions are met. However, the primary earbud (bud A) has an unacceptable LAT. Therefore, at 508, the primary earbud (bud A) hands over the role of primary earbud to the secondary earbud (bud B).

[0053] At 510, the current primary earbud (bud B) after the handover now communicates directly with the user device and calculates its LAT.

[0054] At 512, if the LAT of the current primary earbud (bud B) is good or better, it is assumed that a handover (from bud A to bud B) was appropriate to avoid audio dropouts. Bud B can continue to serve the role of primary earbud until the handover conditions are met.

[0055] If the current primary earbud (bud B) has a bad or worse LAT at 514, the primary earbud (bud B) may hand over the role of primary earbud to the current secondary earbud (bud A) and method 500 may begin again. To avoid near-continuous repeated handovers when both earbuds have bad LAT, in aspects, after the handover at 514, the primary earbud (bud A) may be required to wait a configured minimum amount of time before handing over the role of primary earbud back to bud B based on an unacceptable measured LAT at the primary earbud (bud A).

[0056] In an aspect, handover at 514 is performed when one or more other handover criteria are met. Examples of triggers for handover include selecting a low battery level (e.g., when an earbud has a battery level below 10%) / powered-off earbud / rested earbud; a higher battery level in one earbud than the other (all else being equal, it is preferable to drain the battery evenly between the earbuds because the primary earbud uses the battery more quickly); handedness preference; and, if no other conditions are met, the right earbud. In an aspect, handover is performed when the secondary earbud (bud A) experiences a change in LQI or RSSI and is good or better. In an aspect, a physical state change, such as when an earbud is removed from the ear, takes precedence over signal quality. Thus, when the earbud serving as the primary earbud is removed from the ear, the remaining earbud becomes the primary earbud.

[0057] 6 illustrates an example handover procedure 600 according to an aspect of the present disclosure. At 602, the right earbud (Bud A) receives audio data from the user device when acting as the primary earbud of the earbud system. At 604, the right earbud (Bud A) determines an acceptable signal quality between the user device and the right earbud (Bud A). The signal quality is determined based on measuring at least one of an LQI or an RSSI of the audio data between the user device and the earbud.

[0058] At 606, the secondary earbud determines that the data has acceptable signal quality between the user device and the left earbud (bud B). In aspects, an acceptable LQI and an acceptable RSSI indicate acceptable signal quality. Acceptable may mean any rating above "good."

[0059] At 608, the LAT of the audio data in the left earbud (bud B) is assumed or estimated to be acceptable based at least in part on acceptable signal quality between the user device and the left earbud. As noted above, the left earbud (bud B) is not functioning as the primary earbud and therefore the LAT cannot be measured or calculated.

[0060] At 610, the right earbud (bud A) calculates that the LAT of the audio data exceeds a threshold when the audio latency variance of the audio data at the left earbud is acceptable. By exceeding the threshold, the LAT is determined to be unacceptable. The LAT is calculated based on the audio data received from the user device by the primary earbud.

[0061] At 612, the primary earbud, based on a calculation, hands over the role of the primary earbud to the left earbud (bud B), so that the left earbud (bud B) functions as the primary earbud and the right earbud (bud A) functions as the secondary earbud.

[0062] At 614, the left earbud (bud B) calculates that the audio latency variance of the audio data received by the left earbud, acting as the primary earbud, from the user device is unacceptable.

[0063] At 616, the role of primary earbud is handed over to the right earbud (bud A) based on the calculated unacceptable LAT of the audio data received by the left earbud (bud B).

[0064] As described herein, it is important that handover decision algorithms responsible for driving handover changes accurately predict audio dropouts before they occur. Accordingly, aspects describe methods and earbud systems that advantageously avoid unnecessary audio dropouts by making handover decisions based at least in part on predictors. In aspects, the assessed state of the system may be used to assess not only signal quality metrics but also audio latency variability.

[0065] Numerous uses of, and departures from, the specific devices and techniques disclosed herein may be made without departing from the concepts of the invention, and the invention should consequently be construed as embracing each and every novel feature and combination of novel features disclosed herein.

Claims

1. 1. An earbud system comprising: a right earbud and a left earbud; the right earbud, when acting as a primary earbud of the earbud system, wirelessly receives audio data from a user device, requests specific audio data packets from the user device, and wirelessly communicates with the left earbud, which functions as a secondary earbud of the earbud system; The earbud system, wherein the right earbud performs a procedure to hand over the role of the primary earbud to the left earbud based at least in part on an audio latency variance of the audio data.

2. The earbud system of claim 1 , wherein the audio latency of the audio data received by the right earbud is a volatile proxy for buffered audio in the right earbud.

3. The procedure comprises: determining an acceptable signal quality between the user device and the right earbud; determining an acceptable signal quality between the user device and the left earbud; assuming that an audio latency variance of the audio data at the left earbud is acceptable based at least in part on the acceptable signal quality between the user device and the left earbud; calculating, by the right earbud, that the audio latency variance of the audio data received by the right earbud exceeds a threshold when the audio latency variance of the audio data at the left earbud is acceptable; and handing over the role of the primary earbud to the left earbud based on the calculation, such that the left earbud functions as the primary earbud and the right earbud functions as the secondary earbud.

4. The procedure comprises: calculating, by the left earbud, that the audio latency variance of the audio data received by the left earbud acting as the primary earbud from the user device is unacceptable; and handing over the role of the primary earbud to the right earbud based on the calculated unacceptable audio latency variance of the audio data received by the left earbud.

5. The earbud system of claim 3 , wherein the signal quality comprises at least one of a link quality indicator (LQI) or a received signal strength indicator (RSSI).

6. 10. The earbud system of claim 1, wherein the earbud of the earbud system performing the role of the primary earbud calculates an audio latency variance associated with the primary earbud based on the audio data received from the user device.

7. 7. The earbud system of claim 6, wherein the earbud of the earbud system functioning as the secondary earbud estimates an audio latency variance associated with the secondary earbud based at least in part on a signal quality between the secondary earbud and the user device.

8. 1. A method performed by an earbud system, comprising: receiving, at the right earbud when acting as a primary earbud of the earbud system, audio data wirelessly from a user device; and performing, by the earbud system, a procedure to hand over the role of the primary earbud to a left earbud of the earbud system based on an audio latency variance of the audio data received by the right earbud.

9. Performing the steps includes: determining an acceptable signal quality between the user device and the right earbud; determining an acceptable signal quality between the user device and the left earbud; assuming that an audio latency variance of the audio data at the left earbud is acceptable based at least in part on the acceptable signal quality between the user device and the left earbud; calculating, by the right earbud, that the audio latency variance of the audio data received by the right earbud exceeds a threshold when the audio latency variance of the audio data at the left earbud is acceptable; and handing over the role of the primary earbud to the left earbud based on the calculation, such that the left earbud functions as the primary earbud and the right earbud functions as the secondary earbud.

10. The procedure comprises: calculating, by the left earbud, that the audio latency variance of the audio data received by the left earbud acting as the primary earbud from the user device is unacceptable; 10. The method of claim 9, further comprising: handing over the role of the primary earbud to the right earbud based on the calculated unacceptable audio latency variance of the audio data received by the left earbud.

11. 10. The method of claim 9, wherein the signal quality comprises at least one of a link quality indicator (LQI) or a received signal strength indicator (RSSI).

12. determining the acceptable signal quality between the user device and the right earbud includes determining that the audio data has an acceptable link quality indicator and an acceptable received signal strength indicator; determining the acceptable signal quality between the user device and the left earbud includes determining that the audio data has an acceptable link quality indicator and an acceptable received signal strength indicator.

10. The method of claim 9.

13. calculating, by the earbud of the earbud system acting as a primary earbud, an audio latency variance associated with the primary earbud based on the audio data received from the user device; The method of claim 8 further comprising:

14. and further comprising: estimating, by the earbud of the earbud system functioning as a secondary earbud, an audio latency variance associated with the secondary earbud based at least in part on a signal quality between the secondary earbud and the user device; performing the handover is further based at least in part on a comparison between the calculated audio latency variance and the estimated audio latency variance. The method of claim 13.

15. determining an acceptable signal quality between the user device and the right earbud and an acceptable signal quality between the user device and the left earbud; performing the procedure is based on the acceptable signal quality between the user device and the right earbud, the acceptable signal quality between the user device and the left earbud, and the audio latency variance of the audio data received by the right earbud. The method of claim 8.

16. 1. A method performed by an earbud system, comprising: receiving, at the right earbud when acting as a primary earbud of the earbud system, audio data wirelessly from a user device; determining that each of a link quality indicator (LQI) and a received signal strength indicator (RSSI) of the audio data from the user device to the right earbud is acceptable; determining that each of the LQI and RSSI of the audio data is acceptable in a left earbud of the earbud system; determining that an audio latency variance of the audio data at the right earbud becomes unacceptable; and and performing, by the earbud system, a procedure to hand over the role of the primary earbud to the left earbud of the earbud system based on the acceptable LQI and RSSI in the right earbud, the acceptable LQI and RSSI in the left earbud, and the audio latency variance of the audio data received by the right earbud becoming unacceptable.

17. determining that after the procedure, an audio latency variance of the audio data in the left earbud acting as a primary earbud becomes unacceptable; and determining that a handover condition is met; performing, by the earbud system, a procedure for handing over the role of the primary earbud to the right earbud based on the audio latency variance of the audio data in the left earbud becoming unacceptable and the handover condition being met; 17. The method of claim 16, further comprising:

18. The handover condition is: The method of claim 17 , including the right earbud being the preferred dominant earbud of the earbud system.

19. The handover condition is:

18. The method of claim 17, comprising determining that at least one of the LQI or the RSSI in the right earbud has improved.

20. 17. The method of claim 16, wherein the audio latency of the audio data received by the right earbud is a volatile proxy for buffered audio in the right earbud.

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