Could it be a PSU failure? What are the other components on your computer? Is this a desktop or a laptop?
I'm not sure - though if it were a PSU, would other hardware be affected? So far it's only been the DVD drive. I work on a Win 7 PC desktop. It has only happened once, so far, of course the time when I needed it the most, it may have happened more than that, I don't use the drive a heck of a lot.