I've got a SIP gateway connected to FreeSWITCH with only support for G.711.

I want to have clients only use OPUS codec - as this seems best for mobile data connections.

As of now client <-> FS <-> client use OPUS, but whenever the SIP gateway is involved G.711 is chosen.

If I disable G.711 codec on the client side, to force OPUS, I'm not allowed to dial out via my SIP gateway. So transcoding to G.711 does not occur.

My fs_cli reports this:

Hangup sofia/external/+4413265874 [CS_CONSUME_MEDIA] [SERVICE_NOT_IMPLEMENTED]

Again, reenabling G.711 in the client and everything works.

I have not set disable-transcoding=true.

What to do?