My 12X changer works as well as it needs to. I burn CD's at max speed (52x) using a burning studio not microsoft. The only problem I've encountered was with the inkjet printable cd's. The inkjet printable thickness was too much for the player and I had to use a knife to push the disks back into the cartridge to get the cartridge out.
You may want to try cleaning the laser lens. I have a disk with brushes on it and it has reserected many CD/DVD devices. Unless of course it's more serious than disks/media skipping.