I've successfully got the channel from phone->PBX working on G279. I'm just trying to get the PBX->trunk to also be G279.
I did this by using FreePBX and putting in allow=g729,ulaw into each extension. As I'm using FreePBX and no asterisk expert I wanted to avoid editing sip.conf if possible.
The question is, how can get the same effect for the trunk?