How old is it? Unofrtunately I've never known a Sony DVDRW to last longer than 6 months without rapping out. Maybe it's just chance but I've seen too many to be comfortable with them anymore. They don't even use their own burners in Sony VAIO computers; they use Pioneer DVDRWs!
Try disconnecting the cables from it, boot your computer. Make sure it doesn't show up in dev manager. Shut down, reconnect the drive and see if it changes. Probably not, but then you will know it is most likely the drive and not some other problem.