One way speech over SIP trunk.

[Pompies]

Client has a SIP trunk through IS and has the following issue.

• If we call a switchboard and select an option (eg: press 1 for maintenance, press 2 for accounts etc.), we select a number, it rings, when the person answers, they cannot hear us.
• If we call a supplier such as BT, where the automated voice asks us to explain why we are calling in a few short words, we explain, it asks us to confirm what we said, then it will say, if what they heard is correct, press 2, then it starts ringing and when someone answers, they cannot hear us.
• If we call a switchboard, listen to all the options and wait for it to say: you have not selected an option, will be put you through to an operator, it then works, and they are able to transfer us.

I suspect it might be a setting in the SIP peer profile.

 

[M1tel]

Physical or virtual?

 

[wireman50]

Its not an answer but a clue. The first two scenario's you have sent something to line and for some reason the path back to you is being corrupted. The third one is because you have NOT sent anything else to line and the path back to you is not being corrupted and hence works.

I suspect something at the service provider end.

But as you say it could be something in the SIP Peer profile settings.

What release of software?

 

[Pompies]

Turned out to be an issue on the Service Providers side. Thanks for the help.