One-way audio issue.

[AshishKushwaha]

Hello everyone,

I’m looking for assistance with an issue I’m currently facing. I have a 3CX system installed on a Hyper-V virtual machine. After adding a new SIP trunk, I’m experiencing one-way audio on live calls. During the call, I’m unable to hear any audio from the other party. However, when I check the call recordings, both sides of the conversation are present and recorded correctly.

Has anyone else encountered a similar issue, or does anyone have any suggestions on how to resolve this? We’ve already tried all the common troubleshooting steps and solutions found online, but the problem persists.

Any help or guidance would be greatly appreciated!

 

[Alphabetic]

What is the endpoint and what firewall restrictions are in place?

Have you tried web/mobile client?

 

[AshishKushwaha]

We are currently using SIP lines from our provider, which are delivered over a private IP. From there, we forward the traffic to our 3CX system. We have already allowed all the required media IPs, SIP ports, and RTP ports on the firewall as per the provider's specifications.


The calls are successfully initiated, and in the packet captures (PCAP), we can see the RTP stream flowing with audio that is audible when reviewed. However, during live calls on our 3CX WebClient, Mobile App, and Desktop App, we are unable to hear any audio.

 

[Alphabetic]

What codec are you using?

 

[AshishKushwaha]

provider is sending on G 711u

 

[Alphabetic]

Does your FQDN use external IP or internal IP?

Are you able to use call monitoring and check that?