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Odd 7960 phone rebooting problem...

The problem is with one particular 7960 IP phone. The phone reboots a few seconds into a conversation, but it only does it when it's called from certain callers everytime. Some of the calls are from the PSTN and some are local extensions within the same system. All other calls work fine. Has anyone else ever seen this?


Re: Odd 7960 phone rebooting problem...

Any errors in application log?


Re: Odd 7960 phone rebooting problem...

I just saw a field notice that might apply:

Title: Cisco Field Notice: FN - 62121 - CP-7940G and CP-7960G May Reboot if Volume is Set to Maximum

Summary: The IP Phone may reboot if volume is set to maximum, a call is placed to it,

and the caller makes a loud noise.

Check the volume on this phone, maybe those specific callers have louder voices or something.

Mary Beth

Hall of Fame Super Red

Re: Odd 7960 phone rebooting problem...

Hi Mary Beth ... Thanks for the excellent information.What a strange trouble and one that would be nearly impossible to troubleshoot. It reminds me of a problem I once had on an Octel voicemail system where certain female voices would activate the "dial 0" funtion by approximating the DTMF tone of pressing the 0 key.

Thanks again!! Rob


Re: Odd 7960 phone rebooting problem...

System log should show the reason code for phone unregistration. Look up reason code here

This is for 4.1 version.

Check the pins in the phone jack to make sure they are not bent or damaged.

Also this could be bugs in CM, in phone firmware, or just bad phone.

New Member

Re: Odd 7960 phone rebooting problem...

I checked the app logs and the phone just shows that it unregistered with CM whenever it reboots. There aren't any other errors showing up in the logs concerning the phone. The problem isn't with the volume either. I've used the phone in various locations on our campus with different DNs assigned to it and for the most part it works fine, but when certain callers call the phone, it just reboots without warning. Some of the problem calls are internal and some are from off-campus, but certain calls from the same callers always result in the phone rebooting.

Sorry for the long delay in getting back, I've been tied up with many other projects for a few days.

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