Hi have problem in my Panasonic 1232td system
Strange noise in intercom mode when open the speaker or lift the handset
The noise is appearing in the music on hold and in the door 30865
The only solution to fix this is to replace the cpu
Any suggestion how to fix the problem in the cpu card ??
Regards

What kind of noise is it? How do you know it's the KSU? You may be right....but this could also be a wiring problem, dirty power, interference or a combination of all.

If it's truly the KSU, just replace it....I can guarantee you that will cost less than any of the individual boards/cards inside the unit.

if your ksu is not grounded ground it do you have dimmers for your lights ?