I had a similar problem to this which also continually emptied the buffer on write. It turned out to be the DMA mode for the CD. Go to device manager/IDE ATA controllers, secondry IDE channel (presuming the CD is on the secondry channel) and check that "DMA if available" is in the transfer box. If it has PIO mode only then this is the problem. Change to DMA and reboot, if this has'nt cured it (it did'nt at first in my case) then delete/uninstall the secondry IDE channel. Reboot, windows will re-install the channel and hopefully bobs your uncle all should be well.