Preview Hangs

Hello All

I recently experienced a annoying problem with my Movie Maker. The preview
for the video clips hangs.

To Reproduce:
- New Project
- Import Video clip
- Drag video to timeline
- Play video, video plays just fine
- Click anywhere in the video timeline to forward to a point in the video
(sometimes I have to split the video to make the preview hang)
- Preview of the video freezes but the time line animation continues

Is this a know problem? Is there a hotfix?

Thanks

Linus