I have a Toshiba 5-disc DVD changer. I'd probably just take it in to get it fixed, but before I do and end up paying an arm and a leg (cuz the DVD changer was a win from a drawing so it came as is), what could it be.

It's basically become a VCD player. It gets disc read errors on any normal DVD (not DVD-R) I put into it.

It started cuz there was a mechanical error with one of the gears on the disc table. so I went in and fixed it. No prob there anymore. and once I put everything back the way it was, this occurred. It starts up perfectly fine like it did before all this and no more mechanical errors. It just won't read DVDs. Some help is appreciated.