| It's most likely just dirty and needs some lube. Caig makes excellent products, their 'fader lube' is probably what you need, I use Caig DeOxit quite often, you just spray/pump some into the gap near where the wires solder on. I've also used Radio Shack cleaner/lubes with no ill results. I also used trumpet 'valve-oil' with good results, a friend is an amp tech, and he recommended that, -works great if you've got some lying around (but not for amp pots). Don't use just any electrical cleaner, some are too harsh and can melt plastic parts. | 
