[Freeswitch-users] Reinvite Issue / no SDP

[Stefan Kainz 1012]

Hello,

We're using Freeswitch 1.4.18 on Debian 8.
We ran into a problem with internal call transfers, when the PBX sends a
re-invite without SDP offer.

The Problem is as follows:

1) PSTN -> Freeswitch -> PBX -> Call is answered on extension 100, Audio
in both directions
2) Extension 100 does an unattended transfer to extension 101
2.1) PBX sends a re-invite without SDP. Freeswitch offers SDP in OK message
3) PBX acknoledges the OK message
4) Freeswitch is sending media as announced in SDP Offer, but PBX doesnt
"receive" the audio. Also, no media from the PBX.

Since we're a little desperate, we already tried the following settings:

1) 3pcc-enable true/false/proxy
2) inbound-late-negotiation is set to true
3) renegotiate-codec-on-reinvite true / false
4) disable-transfer true / false
5) enable-soa true / false ( it acutally does work when set to false,
but the call gets hangup after a few seconds of audio - ack timeout )

We also tried to enable bypass_media, so that freeswitch doesnt mess
with SDP.
So, the SDP Offer is generated by a Sonus Media Gateway - still no luck.

Any of you had some experience with such behavior?
We would be very thankful for every advice!

have a nice day!

Stefan Kainz