Providing VOIP barge-in support for a half-duplex DSR client on a full-duplex network by buffering, in a half-duplex DSR client, input audio from the full-duplex network; playing, through the half-duplex DSR client, the buffered input audio; pausing, during voice activity on the half-duplex DSR client, the playing of the buffered input audio; sending, during voice activity on the half-duplex DSR client, speech for recognition through the full-duplex network to a voice server; receiving in the half-duplex DSR client through the full-duplex network from the voice server notification of speech recognition, the notification bearing a time stamp; and, responsive to receiving the notification, resuming the playing of the buffered input audio, including playing only buffered VOIP audio data bearing time stamps later than the time stamp of the recognition notification.