We're using a major VoIP terminator and finding that on many outgoing calls, Freeswitch hangs up with INCOMPATIBLE_DESTINATION after trying to negotiate codecs. The carrier offers PCMA, and it looks like Freeswitch refuses to accept anything but PCMU: 2014-06-06 13:18:54.115197 [NOTICE] sofia_media.c:92 Pre-Answer sofia/external/0011104555493618652! 2014-06-06 13:18:54.115197 [DEBUG] switch_channel.c:3277 (sofia/external/0011104555493618652) Callstate Change DOWN -> EARLY 2014-06-06 13:18:54.175210 [DEBUG] switch_core_session.c:1005 Send signal sofia/external/0011104555391494140 [BREAK] 2014-06-06 13:18:54.175210 [DEBUG] switch_core_session.c:1005 Send signal sofia/external/0011104555391494140 [BREAK] 2014-06-06 13:18:54.175210 [DEBUG] sofia.c:5741 Channel sofia/external/0011104555391494140 entering state [proceeding][183] 2014-06-06 13:18:54.175210 [DEBUG] sofia.c:5750 Remote SDP: v=0 o=- 313783328916230866 1 IN IP4 81.52.176.165 s=- c=IN IP4 81.52.176.165 t=0 0 a=sendrecv m=audio 25080 RTP/AVP 8 13 101 a=rtpmap:8 PCMA/8000 a=rtpmap:13 CN/8000 a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-15 2014-06-06 13:18:54.175210 [DEBUG] switch_core_media.c:2585 Set comfort noise payload to 13 2014-06-06 13:18:54.175210 [DEBUG] switch_core_media.c:2662 Audio Codec Compare [PCMA:8:8000:20:64000]/[PCMU:0:8000:20:64000] 2014-06-06 13:18:54.175210 [DEBUG] switch_core_media.c:2662 Audio Codec Compare [CN:13:8000:20:0]/[PCMU:0:8000:20:64000] 2014-06-06 13:18:54.175210 [DEBUG] switch_core_media.c:2662 Audio Codec Compare [telephone-event:101:8000:20:0]/[PCMU:0:8000:20:64000] 2014-06-06 13:18:54.175210 [DEBUG] switch_core_media.c:2824 Set 2833 dtmf send payload to 101 2014-06-06 13:18:54.175210 [DEBUG] switch_core_session.c:1005 Send signal sofia/external/0011104555391494140 [BREAK] 2014-06-06 13:18:54.175210 [NOTICE] sofia.c:5868 Hangup sofia/external/0011104555391494140 [CS_CONSUME_MEDIA] [INCOMPATIBLE_DESTINATION] However, our codec settings in vars.xml specify: <X-PRE-PROCESS cmd="set" data="global_codec_prefs=G722,PCMU,PCMA,GSM"/> <X-PRE-PROCESS cmd="set" data="outbound_codec_prefs=PCMU,PCMA,GSM"/> The sip profile uses these settings. Any idea how to debug what codecs Freeswitch is willing to accept? Thanks! +Mark