[Freeswitch-users] RTP Timestamp changes after REFER - Question on RFC conformity
benkokakao at gmail.com
Thu Aug 23 19:04:03 MSD 2012
I had a problem with VOP Softclient(www.voiceoperatorpanel.com) where
the callee had one-way-audio after a call was REFERred to him. After
lots of tracing, debugging and hairpulling i realized the problem lies
in the changing rtp-timestamp when the RTP-stream is switched from the
middleman to the initial call after the REFER. The Softclient was not
able to cope with the changed timestamp and ignored the incoming
RTP-packets, leading to no audio for the callee.
I was eventually able to solve the problem by activating
rtp-rewrite-timestamps on the profile(Also added it to
However, i would like to know if FreeSWITCH/Sofia is working according
to the RFC and if the Softclient is to blame for the problem(So i can
file a bugreport with them).
In this thread, Brian West states that it's ok to skip forward in
timestamps as long as the marker-bit is set:
However, the Marker-bit is not set by FreeSWITCH when the REFER occurs.
I didn't find this stated in http://tools.ietf.org/html/rfc3550(But
"timestamp" is mentioned a lot, so i may have missed it) but there's
this bug-report for Asterisk, where the exact same problem is
described and eventually handled:
Could someone with more insight please elaborate?
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