Specify whether transport protocol in SDP media description uses RTP/AVP instead of RTP/AVPF. Note that RFC4585 mandates to signal RTP/AVPF profile, but it may cause SDP negotiation failure when negotiating with endpoints that does not support RTP/AVPF (including older version of PJSIP), furthermore, there is RFC8643 that promotes interoperability over the strictness of RTP profile specifications.