PRO-2021 Squelch Problem

[GizmoeFreak]

I have been searching on and off for a while trying to find a solution, but so far no luck. I have a Realistic Pro-2021 200 channel scanner. It seems to work fine except for the squelch. The problem is the squelch keeps "drifting". I set it as normal, and a couple minutes later static is back, I adjust it higher, same thing happens, again higher until turning it all the way up does nothing. It is not channel or frequency selective. I am suspecting a leaking capacitor, but have no idea how to track it down.

Has anyone had this problem and know how to solve it. This has been a great scanner until this problem showed up.

Thanks