I have a "no audio" issue with FreeSWITCH with a specific sip supplier, no issue with all others.

What I see is a strange codec negotiation:

FreeSWITCH sends the SDP in the INVITE with:

m=audio 22026 RTP/AVP 18 8 101

The Supplier sends its SDP in the 200 OK with:

m=audio 34020 RTP/AVP 8 0 18 4 101

After that, FreeSWITCH uses the G729 and the supplier uses the PCMA so something is wrong in the codec negotiation. Who is in error FreeSWITCH or the supplier and why?

Thanks in advance.

Stephen