DVD Playback problem

[OzAshie]

Hi all,

Just started playing around with MediaPortal but have run into a minor issue. I can playback AVI files just fine, MP3s and MKV files without any problems. But when I try and play a DVD, or even a DVD ripped to the harddrive (all the VOB files residing on the HDD), the audio is choppy and the video very jittery. At times it is almost as if the movie is being played at about half the normal speed.

However, when I play the same DVD/movie in VLC player (ie not using MediaPortal) it plays fine (though the picture quality is a little worse than expected). Also should mention I have installed and configured ffdShow as per Goose's codec guide

So, does anyone have any hints/tips/ideas why the DVD/DVD rips might be playing fine in VLC but stutters in MP?

System specs/setup:

Intel 3GHz CPU
Gigabyte 8VM800M-775 motherboard
Gigabyte 6600GT (AGP) 128MB video card (with VIVO)
1GB Corsair RAM
Seagate 40GB ATA HDD (System and applications drive)
Seagate 250GB ATA HDD (all media stored on this drive)
Pioneer Dual Layer DVD-RW
Wireless keyboard/mouse (Microsoft branded not sure on the exact model)

Software/OS:
Windows XP Service Pack 3
Windows Media Player 11
Latest MediaPortal release
VLC Player (latest version)
ffdShow (latest version)
Avast Anti Virus
Adobe Reader
iTunes

One other thing I just though of, when I installed MP I did select that I would watch TV through the PC. You would also notice I didn't specify/list a TV capture card. The video card has VIVO and will be using that to play capture/play TV. I haven't got around to testing that functionality yet, but will that work? Does MP recognize the 6600GT as a video input device?

Sorry for the long-ish first post, but any advice/help is appreciated.

Thanks.