You might try Milsek furniture polish. It's an oil, not a wax. It does clean. One of the things it does is get the grungy wax out of furniture. I clean houses for a living, and it's wonderful for woodwork, or furniture. I don't know how it would be for musical instruments. I do know it gets grunge out of wood. It also smells very nice. Oh, and a little dab'll do ya.