Solved strange issue

[Dan Nica]

Hi, so I have this 3CX PBX setup in place, everthing is working fine except that when I call from phone extension to phone extension I can't hear anything, but it is working if I call from 3cx mobile app to EXT phone, it works if I call on the DID (like calling a DID which is assigned on an EXT), and so on, can somebody help me with this? The phones manufacturer is GrandStream witht la latest firmware from 3CX.

Thanks,
Dan

 

[Lee Cramman]

Local install or cloud?

Does the firewall checker pass?

SBC or STUN?

 

[eddv123]

So from your description it sounds like audio is not being passed locally between IP endpoints - this is strange as it is normally external calls that are the issue and very rare - please confirm you are referring to the dialling of the standard extension numbers (such as 301,302 etc if you are using a 3-digit extension range).

If you are using an on-premise solution then please describe the local network in more detail, where the phones and PBX are located and how the call traverses the network (if not a flat network).

As stated above, if hosted how are you setting up the endpoints ? STUN, SBC or VPN. If STUN for example do you have "PBX delivers audio" turned on in each extension ? I would expect this to effect both DDI and local extension if this were the case however.

 

[YiannisH_3CX]

Hello @Dan Nica

As mentioned above if you are using remote extensions with STUN you need to enable the option "PBX delivers audio" under each extensions settings for the phones to be able to have audio when calling each other.

 

[Dan Nica]

Thank you, apparently "PBX delivers audio" wasn't check, now is working

 

[YiannisH_3CX]

Glad to see the issue has been resolved and thank you for updating the thread with your solution.