Merry Christmas everyone! I'm using FS 1.0.5pre9, I think there is a bug in mod_sofia when SDP changed in 200 OK response for INVITE message, the scenario is : A(FreeSwitch) B ------INVITE -------> <----100 Tring-------- <----180 Ring -------- with sdp m=audio 55066 RTP/AVP 0 120 c=IN IP4 10.36.143.76 <----UPDATE ------- with sdp m=audio 45486 RTP/AVP 0 120 c=IN IP4 10.36.143.76 -----200 OK ------> response for UPDATE message <---- 200 OK-------- response for INVITE message, with sdp m=audio 45486 RTP/AVP 0 120 c=IN IP4 10.36.143.76 --------ACK ---------> The problem is, B changed the rtp port in UPDATE message and "200 OK" response message, but FS didn't do update, so it still send and receive data from port 55066. I read the mod_sofia source code and debug log, I found that when get 200OK response ,mod_sofia should update rtp session when sdp information is different of the the pre sdp received in 180 ring response, I'm using proxy_media mode, and I think there is the same problem in normal mode. here is the outbound channel state change log ============================== entering state [received][100] entering state [calling][0] entering state [proceeding][180] entering state [proceeding][200] entering state [completing][200] entering state [ready][200] entering state [completed][200] entering state [ready][200] The problem is in state [proceeding][200], The code is as follow: sofia.c line 3876 if (switch_channel_test_flag(channel, CF_PROXY_MEDIA)) { if (sofia_glue_activate_rtp(tech_pvt, 0) != SWITCH_STATUS_SUCCESS) { goto done; } } Since the rtp session is initialized when 180 RING response received, sofia_glue_activate_rtp will return SWITCH_STATUS_SUCCESS without change any thing, So, I think the code should be as follow 3876 if (switch_channel_test_flag(channel, CF_PROXY_MEDIA)) { 3877 if (tech_pvt->rtp_session && !is_dup_sdp){ 3878 sofia_set_flag_locked(tech_pvt, TFLAG_REINVITE); 3879 if (sofia_glue_tech_proxy_remote_addr(tech_pvt) != SWITCH_STATUS_SUCCESS || sofia_glue_activate_rtp(tec h_pvt, 0) != SWITCH_STATUS_SUCCESS) { 3880 sofia_clear_flag_locked(tech_pvt, TFLAG_REINVITE); 3881 goto done; 3882 } 3883 sofia_clear_flag_locked(tech_pvt, TFLAG_REINVITE); 3884 }else{ 3885 if (sofia_glue_activate_rtp(tech_pvt, 0) != SWITCH_STATUS_SUCCESS) { 3886 goto done; 3887 } 3888 } 3889 } When get 200OK reponse and sdp is changed, we should update remote port and set reinvite flag before call sofia_glue_activate_rtp. Because I'm not so familiy with sofia and mod_sofia's source code, this code is only for PROXY MEDIA mode and doesn't check for codec changed.(in my scenario, only the remote port and ip are changed). Could some fs dev check this problem, and give a offical patch? BTW, I guess maybe mod_sofia is just ignore UPDATE message too. (just ignore it if I was wrong) Best Regards -- Lei.Tang lei.tlfly@gmail.com