For repeated DMA errors. Windows XP will turn off DMA mode for a device after encountering certain errors during data transfer operations. If more that six DMA transfer timeouts occur, Windows will turn off DMA and use only PIO mode on that device.
In this case, the user cannot turn on DMA for this device. The only option for the user who wants to enable DMA mode is to uninstall and reinstall the device.
I had a similar problem this week, my computer crashed a few times and I had to reset my computer while my dvd (benq 1640) was still trying to read a badly burned DVD without success.
At that time I was taking up to 25 min to burn a DVD!Â¸
To fix the problem: I disconnected my external DVD, change my firewire cable port position, uninstalled the firewire enclosure drive and DVD burner from Windows XP device manager and rebooted my computer. Now back to normal speed: under 8min per DVD at 8x.
Hope this helps