[G4] G4 AGP DVD/CD Drive Problem

[valerie]

Inherited G4 AGP 350Mhz (have upgraded to Sonnet 1Gig Mhz). Running OS
9.2.2. G4 had DVD/CD RW drive installed which was already known to have
intermittent problems-sometimes reading media, sometimes not. Decided to
ditch DVD drive and get bog-standard CDRW instead. Have tried 2 now neither
of which will open, however both drives are recognised in System Profiler.

Any help from anyone would be very much appreciated.