> Regarding codec selection, I see a minor difference between the FWD and the local * box test cases, but I know nothing about the negotiation protocol... With FWD, the OK message lists 3 Media Formats:
Bingo...GS chokes with GSM...just disallow it in your sip.conf: disallow=all allow=alaw allow=ulaw
Thank you, very much. That got it working. Actually, I used disallow=gsm as suggested by someone else.
Please forgive my ignorance, but this leaves open questions which are nagging me...
I expected that the SIP dialog would be a negotiation such that the devices agree on a mutually acceptable encoding. And I think it's obvious (correct me if I'm missing any key points) that such a negotiation would involve selecting one of the encoding formats which appears in both lists presented by each side. It doesn't seem reasonable that the GS should just "flake out" as it seems to do, simply because it is offered an option it can't accept amongst ones that it can. Is this indeed what I am seeing, or am I mischaracterizing it?
Also, as I noted earlier, shouldn't * wait for the ACK before spewing the audio stream? It appears to be missing the ACK because it retransmits the OK shortly after it begins sending the RTP data.
These loose ends make me very uncomfortable.
