inbound and outbound calls work but internal do not

[kowalski]

Hi forum
I am trying to get my 3CX setup working but: When I call my SIP Nr from the POTS world it works fine, also when I call a POTS via a internal phone (android client) it works perfect.
But what seems should be much easier, the internal call between to internal clients just works partialy.
If I call an internal extension I hear what i say on the receiving extension but on the calling the device I hear a recurring noise like bzzz bzzz bzzz like 3 bzzz every second, its not an echo thing.
Also when i call my own SIP Nr form an intenal client and answer with the other internal client the same noise occurs.

It seems like 50% of the audio connection works wich is nice but not enough.
I already checked PBX delivers audio in the options section of extensions, but this dind't help.
Firewall is green.
What could be a soulution is that every client gets his own ports forwarded, i hope there is an easier way.
The internal phones i use are a client on a windows10 machine and the second one is an app on a android phone.

Help is very much apreciated, thx , kowalski

 

[leejor]

Require more information about your set up. Is this a hosted PBX? Do you use an SBC, STUN?

 

[kowalski]

Its a standalone solution (Intel NUC)
I forward the port 5090 TCP and UDP ... does this make me use SBC? not sure if i really need this.
As I read my settings I use a fix IP, therefore I dont use STUN.

 

[leejor]

From the sounds of it, the sets and the 3CX server are all on the same network. Is this correct? If that is the case, then for internal calls, the firewall will (should) not used. What type of phones are you using? Is firmware up-to-date?I t might be a Codec issue, if internal calls make use of one different than external calls, but highly unlikely given the sound is not there all the time. You might want to check the 3CX Activity log to see if there is anything out of the ordinary for the calls.

The buxz every 3 seconds almost sounds like a hold reminder tone, perhaps some feature/option on the set?