Hi, We have a softphone client using H.264 codec. When we made a call to FS, we found that the OK response of FS for the INVITE missing something. There is a SDP media attribute like this from softphone client: / Media Attribute (a): fmtp:116 profile-level-id=42000C;packetization-mode=0/ But in the OK SDP of FS, we could't find this info. The softphone client would choose other resolution for this call. We know that the H.264 is a pass through video codec in FS. Our question is that is it possible and how can we add the attribute into the OK SDP? FreeSWITCH Version 1.3.17. Thanks. Jimmy