CUCM7 PSTN Calls dropped intermittently

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Feb 9th, 2010
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Hi All,

I have a client that is running CallManager 7.1.2-20000 and a 2821 (SPservices 124-15.T10) connected to a PRI E1.

Various users are complaining that calls to external users via the PSTN become in-audible at random:

After random amounts of time, while on a external call, only the external party will not be able hear any voice and the call needs to be re-initiated. This occurs whether the calls origionates internally or externally.

The Telko provider is sending calls using a circular distribution channel algorithm on the router and it's configured to send calls using Bottom-up.

Any idea's on things to check would be greatly appreciated.



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markbatts Tue, 02/09/2010 - 08:07
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It sounds like it may well be a bug , i had a quick look through the bug toolkit but i couldn't see anything obvious relating to this issue.

I would suggest that you upgrade the IOS on the gateway first , and if that doesn't work  then firmware on the phone.If the problem persists i'm afraid you might need to log a TAC case.



Mark Doney Tue, 02/09/2010 - 08:20
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One way voice is often a routing issue, so I think you should check your IP paths.  Is there more than one route from phone to gateway ?


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