Unity Connection - One Way audio

[james_be_81]

Hi everybody,

We have a one way audio problem at a new branch site we configured.

When a caller (calling from PSTN trough branch site voice gateway) wants to leave a message, CUC behaves like it does not receive any audio signal et after a timeout(5sec) would replay the prompt.

Same behaviour when a user wants to edit his personnal prompt calling trough the branch site pstn gateway. CUC behaves like it does not receive any audio packet.

Region is set to use g729 between branch site and central site where CUC is located. Voice gateway is MGCP. CUC v7.

CUC to PSTN audio is ok and DTMF signaling as well (user is able to authenticate to his voicemailbox, go trough CUC menu...).

Traces on branch site wan router shows no packet coming from VGW but traces on VGW shows packets leaving. Still have to mirror port on switchto see if it is REALLY coming out the GW.

My guess is that I will not see anything coming out the VGW.

Any other idea?

Thx

James

[Chris Deren · Accepted solution]

James,

1 way audio is 99.9% of the time caused by IP routing issue, ensure you have proper routing configured including correct default GWs along the path between the remote location and the head end location.

HTH,

Chris

[james_be_81]

Hi Chris,

I have done a span and was able to see packets coming and going from gateway with right CUC IP addresses. On the unity connection side, only outgoing packets. No packets received.

I think it is indeed due to routing/application filtering problem.

What is your opinion ?

[Chris Deren]

Definitely sounds like IP routing issue, you should ensure that the GW has proper default GW configured and that all L3 devices between the GW and the servers are properly configured for routing.

Chris