Working on my Selmer Treble & Bass MkII. The internal components appear to be all original except for the main output caps. There are some smaller caps on the board that are oval shaped and almost clay-like in texture. One of them was slightly chipped on the clay-like coating and it flaked off. Amp still works but I'm just wondering if this should be replaced. What sort of cap would replace this? Not really sure what all of the different types of caps do.