I bought a Philips DVD-RW for myself & my friend on ebay not too long ago. My drive is working fine but not my friends. On both drives at the back theres no pins where it says 'AUDIO' Could this be causing the problem? The jumper setting on the back of it is fine, its SET to Master.

His PC spes are:
Philips IQon
1248mb DDR RAM
32mb SiS Graphics cardI gather you are saying that both optical drives are identical. If so remove yours and install his in your computer in the precise manner yours is installed. You do not need to remove yours to do this. Nor do you need to physically install his in a bay. Just place it on a stable object and try it. If it works then there is most likely a software configuration on his that is not ADEQUATE. Unless he already has another optical drive on the same cable. In which case "master" would not be appropriate. All this is based on both being not SATA drives (other than the switch i suggested). If they are SATA different ISSUES might be INVOLVED. I assumed NON sata as you have the ability it seems to select master/slave /cable.truenorth