Hi, My configuration is SipPhone<----->asterisk1 <----->asterisk2. My asterisk version is 1.2.10. I installed chan_h323 according to 'http://astrecipes.net/?n=102'. When i call from asterisk1 to asterisk2, there is no audio. Using 'rtp debug', I can see that rtp packets are being received. Regards, Jason. #------h323.conf for both------------------------ [general] port = 1720 bindaddr = 0.0.0.0 disallow=all allow=ulaw context=default #------dial plan of asterisk1-------------------- exten => *59,1,Wait(1) exten => *59,2,Dial(H323/3500@192.168.1.150) #------dial plan of asterisk2-------------------- exten => 3500,1,Playback(hello) exten => 3500,2,Hangup() #------'rtp debug' messages---------------------- Raw PDU: 08 02 55 13 62 1c 00 7e 00 0f 05 28 10 01 00 04 ..U.b..~...(.... c0 01 80 05 01 03 28 00 01 ......(.. 2:15:36.845 H225 Caller:89bf340 h323.cxx(4301) H323 InternalEstablishedConnectionCheck: connectionState=EstablishedConnection fastStartState=FastStartAcknowledged Got RTP packet from 192.168.1.232:16426 (type 0, seq 1540, ts 161645797, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1541, ts 161646037, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1542, ts 161646277, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1543, ts 161646517, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1544, ts 161646757, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1545, ts 161646997, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1546, ts 161647237, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1547, ts 161647477, len 240) Got RTP packet from 192.168.1.232:16426 (type 0, seq 1548, ts 161647717, len 240) ____________________________________________________________________________________ Sponsored Link Don't quit your job - take classes online www.Classesusa.com