No picture in WMP12

Question

Hi everyone,

I have a weird situation here.
If I want to play a MPEG2 Program Stream via HTTP with the WMP12 I won't get any picture, only sound. Now, if I save the stream (*.ps, via VLC) and then view it with WMP12, I get to see the picture without problems.
So it seems that the problem lies within the source filter (DS File Source (URL)). But the really strange thing is, that it actually used to work... After a Windows 7 re-installation the problem mentioned above suddenly appeared.
Another possibility would be, that the EVR isn't used properly in WMP12, but with Media Foundation EVR should actually be the default Renderer, correct?

Any ideas?

PS: The PS contains H.264 content with MPEG2 audio. That's why I want to decode it directly with the Microsoft DTV-DVD Video Decoder which is provided in Win7.

Thank you.