I have a toshiba satellitte c655, and my dvd drive stop reading discs a couple months ago, but the burner still worked, now the burner is only working about 50/50, i understand that the drive itself is probably going, I wanted to know if there is anything else to try before, replacing it, and how much a replacement drive might cost. I live in the northeastern us, if that helps. thanks for your help

You could try a lens cleaning kit. If that doesn't work then the laser/s are wearing out and the drive needs to be replaced. Look at the link below for resellers.
