I'm posting this here because nobody seems to have an answer My Desknote 901A notebook contains an IDE Matshita DVD-ROM SR-8176 MR38 drive. I used the Rpcmgr program from here to set the region code to 1 (I don't plan on buying many DVDs thanks to region coding). /dev/dvd is a symlink to /dev/cdrom which is a symlink to /dev/hdc. The permissions on /dev/hdc are set like this:

brw-rw-rw- 1 root disk 22, 0 2001-04-14 17:43 /dev/hdc

The following relevant packages are installed:
ii liba52-0.7.4 0.7.4-1 Library for decoding ATSC A/52 streams.
ii libdvdcss2 1.2.5-0.2 Simple foundation for reading DVDs - runtime
ii libdvdnav1 0.1.3-1.2 The DVD navigation library
ii libdvdplay0 1.0.1-5 a portable abstraction library for DVD menus
ii libdvdread2 0.9.3-2 Simple foundation for reading DVDs.
ii libdvdread3 0.9.4-3 Simple foundation for reading DVDs

I'm able to mount the drive fine and can even open the .vob files and play them but it doesn't play well at all even though my processor is plenty fast. When I try to play the DVD using Xine, Ogle, and others I get error messages like this:

libdvdread: Using libdvdcss version 1.2.5 for DVD access
libdvdread: Can't seek to block 256
libdvdread: Can't seek to block 256
libdvdread: Can't open file VIDEO_TS.IFO.

With MPlayer I get errors like this:

gmplayer dvd://1
.
.
.
Playing dvd://1
Reading disc structure, please wait...
libdvdread: Can't seek to block 256
libdvdread: Can't open file VIDEO_TS.IFO.
Can't open VMG info!

I'm out of ideas aside from flashing the firmware on the DVD-ROM but can't imagine that would even accomplish anything. Is there something I'm missing? I'm totally out of ideas. Google has provided some leads, but nothing that has worked. The DVD disc works fine in other players so that isn't the problem. Any suggestions and ideas would be appreciated.