What the hell?

My DVD drive (DVD+/-RW NEC ND-3550A) has gone flaky. It will still play DVDs, but if I put in a music or data CD it just spins for a while and won't recognize that there's anything on it. For that matter, I just tried to burn a CD to see if that would jolt things in to functionality, and it won't recognize that there's a CD in there at all. Any thoughts from the tech savvy people among you on how to fix this problem, or did half of the functionality of my drive just die on me?