win xp sets my drives to PIO mode!!!

[davros]

After trying to read a disc burned on a pevious writer or trying to read a disc which is dirty or damaged in any way windows xp pro sets my dvd drive (liteon ) to PIO mode. If I go to device manager and try to set it back by choosing auto detect for dma it has no effect. It has a real impact on the way the drive reads the discs......it really is much faster using dma. Anyway the only way round this to date I can use is to uninstall the IDE channel the drive is on and re-boot causing windows to detect it again on startup and selecting dma again until it reads a disc it doesnt like and starts it all over again.....has anyone had this problem or knows a fix????...cheers!