Good morning, I have a FreePBX 15.0.37.9 we replaced the Tim router and I have one way audio problems can someone help me thanks
FreePBX 15 is end of life.
What is the NAT environment (e.g. PABX and extensions fully inside private LAN and provider on public address)?
Where is the media going missing? (PABX to inside, PABX to outside, outside to PABX, inside to PABX).
Does the SDP contain the correct media address for both ends of all legs, if not which are wrong?
Have you checked that SIP ALG is disabled?
Which version of Asterisk?
Is this SIP (as against IAX or H.323)?
If SIP, which channel driver is in use?
Do you have explicit port forwarding for the Asterisk RTP range from outside NAT to inside NAT?
Note many of these will require you to check logs, so providing minimally redacted version of those will probably help people.