Some Audio CDs don't play in my computer

Hi

I have a half decent computer running WIN XP. For some reason some purchased audio CDs don't register is being in the DVD/CD drive, it's a very small number but it's always the same CDs.

I don't think it's copy protection because of the variety of ages and record companies involved. Not to mention that my understanding is that copy protection degrades the sound of the copy, rather than hide the CD from the drive.

And I don't think it's the hardware or software because the majority of my CDs play fine.

And it's not dirty discs - I can take them out the plastic wrap and stick them in the drive and XP doesn't register their existence.

Anyone have any idea what's going on? I've tried Nero, WMP, Feurio and EAC and none of the detect the CD, so it's at the OS level I guess. Hunted the web and haven't seen anyone report the same behaviour.