Why do you list both as CD-ROM drives? Device Manager should state the model and type of drive in each case.
Dirt is unlikely to be a cause - drives are very well sealed apart from the short time the tray is open.
Have you checked all the leads and connections for firmness?
If these appear correct (and the drives are correctly listed in Device Manager) then uninstall both in Device Manager, reboot and Windows should Find New Hardware and reinstall the basic CDROM driver for each drive (all that is required - Roxio controls the use for burning purposes).