Thanks so much! I ended up making a blend of vinegar and lemon juice that took the tarnish right off, leaving everything perfect. However, in the process of pulling the paddle knobs off, I loosened the posts on two of the 5-way switches behind them. Everything still works fine, but there's just a little in-and-out wobble now (I can pull the knobs away from the faceplate about a centimeter or two, in a way that they couldn't be pulled before). Given that there's a linear actuator between the knobs and the actual switches, am I right in assuming that it shouldn't affect the sound in any way? Best regards.