I don't often dive into these guys, but this was an unbeatable bargain at my local thrift store, including the cassette deck and tuner-amp and remote. The CD changer seems to be able to get itself in a position where none of the disc carriers is loaded into the play section and at the next selection of anything in the disc handling side of things (tray open / play.....) it displays error. A judicious prod on the gear trains after power cycling and making the next selection usually gets it back into normal operation for a few cycles. I have the service manual, which provides disassembly instructions for what I'd go for if someone hasn't already been and solved this, i.e, open up, remove old grease and reassemble with new grease. Or is it more likely to be the tray belt slipping? I'd put that second as the trays drive nicely 90% of the time. Any thoughts? Thanks!