sound ok but no video, no dvd picture

[matis1]

TV-Server Version: 0.2
MediaPortal Version: 0.2.2.0, SVN 2.5.07
MediaPortal Skin: blue two
Windows Version: xp pro sp2
CPU Type: Intel Pent4, 2666 Mhz
HDD: samsung, seagate 160mb
Memory: 512mb ddr sdram
Motherboard: aopen AX4PE Max
Motherboard Chipset: Intel Brookdale i845PE
Motherboard Bios: Award (04/01/03)
Video Card: ATI Radeon 9600 XT
Video Card Driver: 6.14.10.6683
Sound Card: Intel 82801DB ICH4 - AC'97 Audio Controller
Sound Card AC3:
Sound Card Driver: 5.10.0.5190
1. TV Card: hauppauge 350 pvr
1. TV Card Type: analog
1. TV Card Driver: 1.18.21.23257
2. TV Card: technisat skystar hd
2. TV Card Type: dvb-s2
2. TV Card Driver: 4.4.10.18
3. TV Card: Hauppauge nova td usb
3. TV Card Type: dvb-t
3. TV Card Driver:
4. TV Card:
4. TV Card Type:
4. TV Card Driver:
MPEG2 Video Codec: dscaler
MPEG2 Audio Codec: dsaler
Satelite/CableTV Provider: Astra c
HTPC Case: antec
Cooling:
Power Supply:
Remote:
TV: , Benq-projector, Sony
TV - HTPC Connection: RGB, S-Video


i believe it is NOT an mp issue but nevertheless i need your help.
im not sure when it started, i did a little bit of installing - deinstalling during the last days....
when playing a dvd or also a mpg-video i get sound but no video signal. strange thing is that i can see the video playing when in home screen of mp (just in the lower left corner - not sure how this preview is called).
i have the same not-working situation trying to play videos in power dvd 7, and in nero.
hardware manager says no problem with the graphics card.
also in the catalyst setup in the video section i get no picture for instance in the color calibration card. also in cyberlinks system diagnosis i get no picture.
i installed the latest drivers for my radeon 9600, i did a reinstall of directx9.0c.
no change - i have no idea how to go on in diagnostics or therapy...
can anyone give me some tips?

[matis1]

i just found out that with a graph setting like this (attached) everything is working fine in graphedit, i can even wath my dvd and the video at the same time...

im a very dummy in graph editing so there are several questions for me:

why do the cyberlink filters affect the function as they are not attached to anything in the filterline?
do i have to save this graph in order to make my system functioning again?
can anyone give me a little howto?

thanks in advance for anyone with a good idea

PS: forget about the mpeg splitter, it also works without him... ;o)