I have again a question regarding the codecs negotiation in Asterisk.
I’m using Asterisk 1.8.20.
I have Peer 1 (allow=gsm,alaw) and Peer2 (allow=gsm,alaw).
I have directmedia=no, nat=yes on both peers 1 and 2.
If peer 1 is calling with gsm codec enabled. Everything is OK:
Peer1 – GSM – [Asterisk] – GSM – Peer2
Now if peer1 doesn’t support (on the phone) the codec GSM (disabled or unsupported), then asterisk will chose alaw for peer1 and he will chose gsm for peer2
Peer1 – alaw – [Asterisk] – GSM – Peer2
It results transcoding on Asterisk
Is there a way to avoid this and to say to asterisk to use alaw with peer2 in this case, in place of GSM ?