Just purchased a 2220B locally that is in excellent condition and sounds very nice except for one issue. The "main" speaker button/switch does not work so i have my speakers connected to the remote side. You push in the main button and it does not stay in. I think at one time someone tried to replace it because the silver button part looks to be slightly larger diameter than the other push in switches on the unit, so i gather its from a different marantz model. There is a 2220 (not the B) version set of main/remote push in switches for sale on ebay currently. Does anyone know if these are the same ones used in the 2220B models and interchangeable? Thanks in advance.