Solved Internal calls no sound

[bongoit]

Hi,

We have a client with a 3CX PBX that is having a problem. Calls to external users work well, but, suddenly, internal calls have no sound. This system has been in place and working well for ~6 months.

The PBX is cloud-hosted, not on premise. There is no SBC.

They use Fanvil IP phones provisioned through 3CX. I have updated all the phone firmwares, rebooted the PBX, rebooted the router.

Is there anything else I can try?

 

[ChrisC_3CX]

Hey @bongoit,

Just so that first have a better understanding of your setup, please have a look at the following post and provide the information mentioned: https://www.3cx.com/community/threads/information-to-provide-when-requesting-help.67558/

 

[leejor]

You might try enabling the PBX delivers audio option, per extension, if not already done, as the sets would seem to be using STUN. I assume that each set is using a unique local port. Did anything on your network recently change? how many sets at that location?

 

[bongoit]

"PBX delivers audio" Fixed it for me, many thanks for your help!

 

[leejor]

That is going to force all audio packets back through the PBX, rather than going direct between sets, for internals calls, so while it may work, you still might want to investigate what caused the change.

 

[ChrisC_3CX]

Well, since STUN was the provisioning method, the RTP traffic would not ever be expected to go from IP phone to IP Phone directly, provided of course that the STUN configuration was implemented as per our guides.