I just picked up a Sanyo M9930 in very good condition. I had one in 1979 and forgot how good it sounded. I must have played my RUSH tapes a million times on it. The one I just got is missing the handle, but everything else is working great so far. I can't remember how to use the RCA inputs on the side though. There isn't an input switch anywhere that I can see. Anybody know?