xine/ogle/mplayer slow dvd video output

I've finally figured out how to get these progs to actually play dvd on 
my machine but the video part of the dvd playback is excruciatingly 
slow. I had the same dvd player in a much slower machine under suse7.2 
and things were fine but on suse8.1 it's unwatchable.

xine refuses to see my dvd if it is set as /dev/hdb, but will play it 
Sloooooowly if I use /dev sr0. Unfortunately this does not allow me to 
turn DMA on for the dvd player.

Actually for some reason none of my drives are allowed to set dma on any 
more, even though they were set up that way right after I installed 8.1

I know I've covered a bit of ground, but I'm hoping that something here 
will ring a bell for someone.

Thanks for your help
dh