Hi, I found that DTMF, AVMD and Talk on/off will only work if RTP stream is running from both sides of the call. What I am doing is using the sampleclient program and making a call. If the sample client is not playing audio then none of these work. As soon as I play an audio file everything works. I need it so all this works on even if I am not streaming audio. RTP from the person I called should still work. Andrew