Hello, the sdp looks ok, assuming that there is an empty line after P-hint header. Perhaps you should test with a sip phone to see if the call is ok with it, if yes, then you have to ask the carrier to give you details about why the call is not accepted. Cheers, DAniel On 8/13/12 9:52 AM, phillman25 wrote: Dear List I am trying to remove specific lines from the following original SDP body: Content-Type: application/sdp Content-Length: 406 v=0 o=root 3048 3048 IN IP4 xxx.xxx.xxx.xxx s=session c=IN IP4 xxx.xxx.xxx.xxx b=CT:384 t=0 0 m=audio 11904 RTP/AVP 0 8 18 101 a=rtpmap:0 PCMU/8000 a=rtpmap:8 PCMA/8000 a=rtpmap:18 G729/8000 a=fmtp:18 annexb=no a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=silenceSupp:off - - - - a=ptime:20 a=sendrecv m=video 11602 RTP/AVP 34 99 a=rtpmap:34 H263/90000 a=rtpmap:99 H264/90000 a=sendrecv I need to remove the following lines from the above SDP body as my International carrier does not support Video capabilities: m=video 15042 RTP/AVP 34 99 a=rtpmap:34 H263/90000 a=rtpmap:99 H264/90000 I used the following code in Kamailio config: if(has_body("application/sdp") && search_body("m=video")){ subst_body('#m=video ([0-9]+) RTP/AVP (.*)$# #'); subst_body('#a=rtpmap:34 (.*)$# #'); subst_body('#a=rtpmap:99 (.*)$# #'); subst_body('#a=sendrecv(.*)$# #'); } Content-Type: application/sdp Content-Length: 325 P-hint: outbound v=0 o=root 3048 3048 IN IP4 xxx.xxx.xxx.xxx s=session c=IN IP4 xxx.xxx.xxx.xxx b=CT:384 t=0 0 m=audio 11904 RTP/AVP 0 8 18 101 a=rtpmap:0 PCMU/8000 a=rtpmap:8 PCMA/8000 a=rtpmap:18 G729/8000 a=fmtp:18 annexb=no a=rtpmap:101 telephone-event/8000 a=fmtp:101 0-16 a=silenceSupp:off - - - - a=ptime:20 a=sendrecv As you can see the m=video body has been removed, however, calls are still failing. Is there something i have missed? I am using Kamailio v3.2.2 Thanking you in advance! Phillip -- Daniel-Constantin Mierla - http://www.asipto.comhttp://twitter.com/#!/miconda - http://www.linkedin.com/in/miconda Kamailio Advanced Training, Seattle, USA, Sep 23-26, 2012 - http://asipto.com/u/katu Kamailio Practical Workshop, Netherlands, Sep 10-12, 2012 - http://asipto.com/u/kpw