[cisco-voip] call quality issues between gateway and Unity

[Kris Seraphine]

Hi

I have a customer with a multi site centralized CCM 4.13 cluster.  The
remote sites are getting complaints of poor voice quality from customers
when being transferred to Unity (which is located in the central site) .
The callers cannot understand the greetings and describe them as choppy.
There are no problems with external calls transferred from the remote sites
to IP phones at the central site or for intersite calls.  It seems to be
limited to calls where the RTP stream is between a remote voice gateway and
Unity.  These calls are G.729 so Unity has to transcode the greetings on the
fly but if that were the problem I'd expect remote users to have the same
problem when calling into check their messages or leave messages for other
users.  Also, the Unity server is not very heavily used; it generally has no
more than 9 active calls at the most.

I suspect the gateway might be the problem.  It's a 2851 running MGCP.  I
guess I'd like to know if anyone agrees or disagrees with this assumption.
Also, I've had a lot of problems with MGCP code on the ISRs.  Can someone
recommend an IOS version that is stable for and MGCP gateway and doesn't
suffer from DSP firmware issues?

I should mention that Unity is version 4.04 sr1 and the gateway is running
12.4(5).

Thanks

-- 
kris seraphine
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://puck.nether.net/pipermail/cisco-voip/attachments/20060911/0df89919/attachment.html