Hi i use caig deoxilt d5... which is a spray cleaner. It works great. I've had 3 way switches that werent working right and pots that were scratchy. After i sprayed them with this cleaner they work fine now.
I use Radio shack Contact/control cleaner & lubricant. I just spray a little in the pot then turn the shaft back and forth a few times and it is as good as new. Works like a charm.