G4 Imac 10.2.8 Superdrive wont read dvd's

but it will burn dvd's through roxio toast 5. It will also recognise CD's, but when insert a commercial dvd or a dvd burnt on the unit is inserted a message reading "You have inserted a disk containing no volumes that Mac OS X can read. To continue with the disk inserted, click Ignore." I have done a verify and repair disk permissions, also a verify and repair disk, but this has not fixed anything.

The latest update to the system was upgrading to version 6.0.4 of Itunes, and as far as I am aware the drive was reading dvd's before this - I suppose - i can't say for sure but I think it was.

Is anyone aware of any issues like this and how I can fix the drive? Could it be that the drive needs a clean?

Any help you can give me will be greatly appreciated.

Thanks and regards

Loki.*

I think the drives have different mechanisms for reading and writing both DVDs and CDs. My PC DVD drive suddenly would only deal with CDs and so I had to get a replacement. You might have to do the same.