Even more than hard drives, optical drives are prone to mechanical failures of all kinds. They are manufactured as cheaply as possible, with plastic gears etc, and unfortunately do not last for ever. Because they are manufactured cheaply, they do not cost much to replace. Having said that, one possibility has occurred to me. If you are using drag-and-drop to burn files to the CD you could have an open session that is keeping the drive in an active state. You can right click the application's icon (such as Roxio DirectCD) in your system tray and select "close" or "eject" (don't select "close" unless your disk is full, or you won't be able to add any more files to it). Or you can open My Computer and right click on your CD drive and select "Eject". if these don't make any difference, the failure is probably mechanical.
