The amp in my 120 was potted in wax when I got it. All along the base of it and around the edges. Had to chip it all out to even get the amp out! Even after cleaning, the amp has a nice waxy residue to it - ick. Was that something original to the piano? I'm asking because I'm trying to chase down some hum, and because there's still some wax that remains on the case, I don't think the amp chassis makes perfect contact with the electrostatic paint, which I would think it would need to.