Hi, I usr freeswitch to call out A & B, and want to bridge calls after A & B responded. After bridging the two call, I found out that the sdp codec negotiated from A and from B are different, e.g., 102 and 111. This will cause A & B codec not sync problem. Is there any way to force clients using specific codec in freeswitch? I have found out some code in switch_core_media.c: /* it could be 98 but chrome reserves 98 and 99 for some internal stuff even though they should not. Everyone expects dtmf to be at 101 and Its not worth the trouble so we'll start at 102 */ smh->payload_space = 102; Seems the codec send to clients always begin from 102? Many Thanks, Leo