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g729 problems

I am having a couple of problems. Maybe they are related,<br> maybe not. <br><br>First I have two routers one connected to the PSTN and the Other to a PBX, both are running G729,and are my gateways for the call manager. So I installed the g729 codec on Unity, however I am still running G711 bewteen IP phones. Now I am having audio problems. I haved look through a bunch of post here in this forum, and have followed their direction. I first had the problem of the prompts being to loud. So I installed the g729 quiet prompts, this made the prompts way to low. So I then installed the g711 quiet promts which seemed better, but they are still to low and they seemed garbled and sound like you are in a tunnel. I have adjusted the record and playback settings in the registry and the messages and custom recordings seem of pretty good quality. Any other suggestions? <br><br>second issue: In the text to speech application, when I call the unity from a ip phone it works fine (except the quality is not that good, but I heard I need SpeechWorks instead of TTS3000 application to fix that)However when I call from the outside going through a g729 gateway, Unity tells me I have an E-mail Message, says "subject", then skips to the date and time failing to read the subject or the body of the e-mail. Also I do no know if this feature worked before I added the g729 codec to the unity.<br><br>So anyway I can see there is something messed up with the convertion to the g729 codec.Any suggestion would be helpful.<br><br>


Re: g729 problems

Can you also post your Unity/TSP/CCM version info?


Re: g729 problems

We are seeing a lot of issues with this in TAC. AGC is on the way but you won't see it in 3.0(1). Usually the problems are with systems that run two codecs. While Unity can technically do this, the two codecs do sound a bit different. Customers usually have the best luck with running just one codec to the Unity and then tweaking the sound. If you have a hardware transcoder you can do this easily and still use G.711 within regions and G.729 between regions. If you don't have hardware trancoders you might want to run G.729 globally. Our largest CallManager/Unity customer chose to do that instead of investing in hardware transcoding. Anyway check out this doc:

As far as your G.729 TTS issues go I bet your on a version previous to Check out the bug CSCae07909 in the release notes:


Keith Chambers
Unity Technical Lead
Unified Voice Team, San Jose
Cisco Systems