No audio with webclient on one trunk

[greychain]

We have just added a new DID to an existing trunk. The trunk and webclient work correctly on the original DID.

The customer is experiencing no audio when making an outgoing call using the webclient.

I have tested from the desktop app on the same desktop and the audio is bi-directional.

I then created a new trunk identical to original trunk and assigned the new DID to it and performed the same tests same result. The original trunk is still working correctly.

Where should I be looking? Which ports does WebRTC use? Which ports does the 3CX desktop app use?

3CX V18 latest update, self hosted

 

[greychain]

Turned out to be a configuration issue with this one PC, tested on another and it's ok.