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New Member

Unity Deadair Message for PSTN calls Over ICT with G.729 Codec

Network Setup: Two locations, US and India . At US location, customer has a Callmanager, Unity, One PRI Gateway on 6500 switch using WS-6608 Module, and IP Phones. This PRI Gateway is registered to US Callmanager.

At India, customer has one Callmanager, Unity and IP Phones.

A intercluster trunk connects between India and US Callmanagers. G729 Codec is used in ICT. Pls find the Network Diagram attachment for details

Problem: When A user call from US PSTN and leave voice message, for a user in India, the message is received as dead air.

When a user call from US IP Phone, he can leave a message for a user in India and it works fine.

User from US PSTN Can leave a voicemail in US Unity server properly.

When Intercluster trunk is configured to Use G.711 codec, User from US PSTN Can leave the message in India Unity properly.

New Member

Re: Unity Deadair Message for PSTN calls Over ICT with G.729 Cod

You are having this issue beause unity only supports G.711. You need to setup hardware transcoding in India to convert the g729 calls to G711 for Unity. Check on adding some PVDMS to you router in India and setting up a DSPFARM. good luck