I have installed a Memorex 16X CD/DVD RW drive into a PowerMac G5 dual 2G tower running Mac OSX 10.4.10 with 4.5G of RAM. When I insert a disc into the drive, it responds normally for a while -- reading and writing to discs without difficulty. However, if I leave a disc in the drive without accessing it for a period of 5 minutes or so, the drive stops responding and I am unable to read, write or even eject the disc. In addition, when this problem occurs, it prevents the Finder from shutting down, so I am forced to manually shut off the computer using the power button on the front of the CPU. I previously had this same drive installed in a PowerMac Dual 1G G4 system without any difficulty. Does anyone know why this might be happening?