Suddenly I have an RTP Issue

General
1

Seems I now have suddenly a Problem with communication between my FreePBX and my Mobile Devices. When my Mobile Phone is in the same LAN as my FreePBX everything is fine. When my Mobile phone is connected to the mobile network only I can dial and ring the extension but when I pick up I can’t talk or hear anything. I know this is an RTP Issue but RTP Ports are allowed in my Routers Firewall. Outgoid rules are all allowed. The FreePBX Firewall ist turned off.

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My Router is a Unifi Gateway Ultra and my DDNS Provider is No-IP.com

Does anyone had a clue on that matter ?

Greetings
Wally

2

Any chance your public IP changed and your outside IP isn’t updated under asterisk sip settings?

3

I checked that. Everything clear and updated

4

There is a lot of possibilities here.
In your FreePBX web gui:

Setting>Asterisk SIP Setting do your RTP Ports match what you have in your Unifi’s Firewall Rules? Standard is 10000-20000.

To attempt to confirm a few things are you using V17,PJSIP, and is your Cleary Anywhere Module set to use UDP or TCP?

5

You can turn on logging in the clearly anywhere app and make some calls then send the log to CIP support.

6

I may suggest to to check the SDP offer of the call using sngrep or tcpdump, if you set up asterisk to use the FQDN and you set the hostname for the server to resolve to itself it can advertise the RTP audio address as 127.0.0.1 causing audio issues, not 100% sure but I recall seeing that one in the wild a few yrs ago

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