Hello,

I have an issue with codec negotiation, seems to me that freeswitch is trying to transcode g729 to g729 annexb=no for some reason, even when I have different codecs available?

I'm bridging 2 calls, with profile settings:
    <param name="inbound-late-negotiation" value="true"/>
    <param name="disable-transcoding" value="true"/>
and dialplan:
    <action application="set" data="inherit_codec=true"/>

with global codec:
  <X-PRE-PROCESS cmd="set" data="global_codec_prefs=PCMA,PCMU,G729,G723"/>

here is invite and 183 progress message:

Session Initiation Protocol (INVITE)
    Request-Line: INVITE sip: SIP/2.0
    Message Body
        Session Description Protocol
            Media Description, name and address (m): audio 20268 RTP/AVP 18 8 0 101 13
            Media Attribute (a): rtpmap:18 G729/8000
            Media Attribute (a): rtpmap:8 PCMA/8000
            Media Attribute (a): rtpmap:0 PCMU/8000
            Media Attribute (a): rtpmap:101 telephone-event/8000
            Media Attribute (a): fmtp:101 0-16
            Media Attribute (a): rtpmap:13 CN/8000
            Media Attribute (a): ptime:20
            
            
Session Initiation Protocol (183)
    Status-Line: SIP/2.0 183 Session Progress
    Message Body
        Session Description Protocol
            Media Description, name and address (m): audio 59852 RTP/AVP 18 0 8 101
            Media Attribute (a): rtpmap:18 G729/8000
            Media Attribute (a): fmtp:18 annexb=no
            Media Attribute (a): rtpmap:0 PCMU/8000
            Media Attribute (a): rtpmap:8 PCMA/8000
            Media Attribute (a): rtpmap:101 telephone-event/8000
            Media Attribute (a): fmtp:101 0-15
            Media Attribute (a): sendrecv
            Media Attribute (a): maxptime:20
            
After that I get error message:

2016-07-13 11:29:11.136011 [ERR] mod_g729.c:102 This codec is only usable in passthrough mode!
2016-07-13 11:29:11.136011 [ERR] switch_core_io.c:1434 Codec G.729 encoder error!

and freeswitch sends CANCEL to B-side leg.

Maybe I have missed my settings, but if codecs "mismatch" shouldn't freeswitch choose g711 a/u and not try to "transcode" the codec?

Best Regards,
Vladislav