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Community Member

Strange FXO Noise problem

Anyone have an idea ?

Since we installed the system 6 month ago, we always got one noisy phone line, which isn't always the same (physically).

The noise is always on the remote end. Meaning that we, locally, on the cisco system, do not hear it. but on the remote end, it sound like frying and boiling.

I though first, that it was a bad line from our telephone provider, but after some diagnostic, we conclude it wasn't.

If i phone out back on our telephone number and pick up the line on another phone, sometime i hear the problem.

Locally, the system is working perfectly. also 5 of the 6 exterior telephone lines are fine on the 2 4FXO cards.

I upgraded the IOS from 12.4(11)XJ3 to 12.4(11)XW2. I did all of the audio tuning and impedance tuning in the book, and it didn't helped....

We already changed the 1st 4FXO card because of a dead FXO port. So the problem is not the FXO card.

I attached my partial config....

Any help would be appreciated

running 2801 spservicek9 12.4(11)XW2

2x 4FXO

Community Member

Re: Strange FXO Noise problem

It may be an issue with the PVDM2 modules. Can you do a "show inv" and a "show voice dsp detail" and see how many and then the firmware version on your PVDM2's.

Community Member

Re: Strange FXO Noise problem

Hi ! Thanks for the reply ....

I attached the file show_dsp.txt

Thanks !

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