For JMD :
the problem you are experiencing is caused by the network not creating the RTP voice path until the answer supervision is received. Since you are using the timer option instead of VAD you will not get a voice path until the timer expires which may be well after the caller has actually answered. There are two solutions. 1) find a way in Clarent to enable the RTP path (in Cisco this would be VOICE RTP SEND-RECV command) 2) Change to the better VAD approach which will cause the RTP to be created when the caller answers. Hope this helps.