Intermittent scratches/distortion/level changes in preamp

[mediatechnology]

I wished I had a good cure for silver sulfide on switches.

With stinky "junk" silver coin I use baking soda in warm water in a glass pan with a sheet of aluminum foil.
It pulls the funk right off.
I would never do that with collectable coins but for junk silver dimes, quarters and half dollars it cleans them up.

Not sure how you could make that work for switches...