SCN Call connects but only hear yourself

[CallMeLB]

I've got a customer with server edition and 40+ expansion units. All units connect to server and then to an expansion unit for outbound calls. Only one branch is hearing themselves when they place calls to extensions on other systems or outbound calls through another systems PRI. They have IP phones and analogue trunks at the local expansion unit and work fine between each other and local outbound calls. Calls to extensions and outbound over the other PRI connect and stay connected but the local site hears themselves and the far end hears nothing.

I've tried adjusting the number of channels on the trunks to force it to reset and supposedly worked once but the issue is back. I feel like it may be network related but not sure how to prove it. Their network team says it's setup the same as other branches and I have no reason to believe otherwise. Any idea's on what it may be, or if it's the network a way I can prove it?

 

[icet500]

Do you have the same set of codecs in the scn line on both ends? try to disable "direct media" from both ends (server and expansion) for lines and IP phone Extension.

 

[RocketJTech]

Yes, as @icet500 suggests, disable all "Allow Direct Media" options. This option allows IP devices to connect without going through he phone system. However, some network equipment (i.e. routers, switches, bridges) do not support this feature and cannot pass the data necessary for the exchange. Disabling this feature requires the connection to "pass through" the phone system, but should fix your issue. Good luck.

Thanks to technology, we can instantly communicate across the world, but it still doesn't help us know what to say.

 

[CallMeLB]

Yes, codecs being used are G729 on all ends and all Allow Direct Media is unchecked.

 

[CallMeLB]

Correction, I found one side had G711A set as a codec. Waiting for reboot approval to confirm that is the issue.