I have a two asterisk server. Server A is running asterisk 1.62 on a vps server and Server B is running on a normal pc with tdp400 fxo card. I have a sip trunk (g729) trunk with another operator. Call is coming from him to server A and send that call to server B via another sip trunk (g729) and that call is send via server B TDM card. This server A and server B connecting via IP sec tunnel. My problem is when call is coming from other person, he complain me the call volume varying time to time. I also observed that the call volume is decreasing during the call.
I change the codecs and tested the scenario. But the result was same. Any one can tell me what can be the problem.