VOIP Phone goes to VM after one ring??

[rhodes4evr]

I have a satellite office that has reported a sporadic issue. When they receive a call it rings one time and goes to VM as they will receive the message a couple minutes later. It happens sporadically 3-4 four times a day out of 50-100 calls received.

My first thought was how many people on the phones at a time and they say it could be 1 person in the office or 5 and the issue will occur.

Has anyone ever heard of this issue.

Is it a callmanager issue or a router issue? The connection to this office is a P2P T1 and we are using a 2800 Cisco Router with a Switch Module.

Thanks,

[Steven Holl]

Sounds like you are running full-blown Communications Manager, and not CME?  No one is hitting iDivert, are they? :-P

Have you looked at a route plan report for that number to make sure there isn't any overlap of it matching a DN in another partition which has a different CFNA setting?

Detailed CM traces for a working call and a non-working call would shed light on what's happening under the hood.