CD drives will not refresh

I have 2 CD drives - neither will refresh their contents - even after maunally refreshing. If I put a new CD in the drive the only way I can see it is to restart the PC. Any ideas?

OS is XP PRO SP 1
CD drives are Lite on (USB) and TDK (internal IDE)
AMD system on DFI Lanparty MOBO

Windows version?

Is autoplay enabled?

I fixed it, but thanks BPB - it seems to have been the program "in cd" by Nero that was doing it.