DVD playback problem, please help!

[TheGTiDude]

I'm having problems playing DVD's on my PC, but not all of them, just some. My drives finds it ok, and even plays them, but with pour audio and no video. This seems to happen with both of my drives (which have been in 2 different computers, and have the same problem). I've even installed a SCSI dvd drive and tested with a friends external sony USB2 DVD-RW drive.

My drives are:
ASUS DRW-1604P (fairly new)
Samsung CDRW/DVD SM-308M

My current video card is a Radeon 7200 series. running on an Abit ktz-raid mobo with a 900mhz Thunderbird processor.

I just find it really odd and frustrating that this only happens to some DVD. For example: my "Spinal Tap" DVD doesn't work but "Without a Paddle" works fine...

I first noticed this problem when I was backing up my dvd collection using anydvd and clonedvd and the movie preview would not come up in clone dvd. Also, if the preview doesn't come up, that usually means that there will be an error durring the clonedvd process.

I've updated my firmwares and drivers.

Can anyone please help!

Thanks