I haven't done this in a long time...but my power amp (solid state) is developing a scratchy vol pot on one side. I remember from a looooong time ago that there were products (like spray stuff?) for cleaning out potentiometers and other stuff. But I also have a vague recollection of someone telling me that using the stuff was a bad idea. Anyone have any comments one what is appropriate treatment for this condition? (Um, the scratchy pots, not the vague recollection ).