stutter on HD / late frame (1 Viewer)

[naich]

MediaPortal Version: MP 1.0. 2
MediaPortal Skin: BlackGlass
Windows Version: XP / Win7 both home and prof
CPU Type: AMD DC 4600+
HDD: 1,5 and 1 TB
Memory: 2 GB
Motherboard: Server / Asus HDMI V2AM
Video Card: Ion onboard
Video Card Driver:
Sound Card: oB
Sound Card AC3: SPIF
Sound Card Driver:
1. TV Card: mediapointer S2 dual low profile
1. TV Card Type:
1. TV Card Driver: latest
2. TV Card: mediapointer s2
2. TV Card Type: latest
2. TV Card Driver: BDA
3. TV Card:
3. TV Card Type:
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec: mpc / PDvD9
MPEG2 Audio Codec: mpa /PDvD9
h.264 Video Codec: H.264 cyberlink / PDvD9
Satelite/CableTV Provider: Astra 19.2°E
HTPC Case: EeeBox EB1012
Cooling: Zalman
Power Supply: BeQuiet
Remote: Asus remote / logitech 885
TV: LG 42' Plasma
TV - HTPC Connection: DVI->HDMI


Hi!

After a few minutes watching a HD channel, the sound and also the picture stutters.

Plz take a look at the logs. There are a lot of errors:
EVR

24-01-2010 16:58:01.308 [8d4]Scheduling sample from the past (307 ms, last call to NotifyWorker: 1 ms)
24-01-2010 16:58:01.323 [8dc]skipping frame, behind 321 ms, last sleep time 10 ms.

TS-Reader

24-01-2010 16:54:38.097 [13dc]Vid/Ref : 2.601, Late I-frame(00), Compensated = 0.000 ( 0.000 A/V buffers=04/03), Clk : 0.000000, State 1
24-01-2010 16:54:38.110 [100c]Aud/Ref : 1.297, Late Compensated = 0.170 ( 0.170 A/V buffers=04/00), Clk : 0.000000, State 1

Cu