stuttering dts playback with 1080p movies

[pascalgeusen]

TV-Server Version:
MediaPortal Version: rc1.0
MediaPortal Skin: xface 1.5
Windows Version: XP MCE 2005 SP2
CPU Type: AMD x64 4200+
HDD: 2×samsung spinpint 500GB 1×samsung spinpoint 200GB
Memory: 2GB PC5300
Motherboard: Acer
Motherboard Chipset:
Motherboard Bios:
Video Card: ATI x300
Video Card Driver:
Sound Card AC3: Theatron Agripa 7.1 DTS
MPEG2 Video Codec:
MPEG2 Audio Codec:
Remote: MCE
TV:
TV - HTPC Connection:

Hello,

I have problems with dts audio playback in 1080p movies. AC3 works fine, but when I am using dts the movie en de audio starts stuttering. I am using the latest CoreAVC video codec for h.264 playback and the ffdshow Audio Decoder and my Theatron Agripa 7.1 DTS for Audio renderer.

Is it something in my audio settings?? I do not want to use the computer for decoding sound. I have a good receivers which has a dts/dd decoder build in. What to do?