[Hunv]

Hi,

I have the same issue but not a low-spec PC.
It is not only by playing movies. It seems that it is everything that is hardware-accelerated.
For Example more programs that have this issue:
Windows Live Messenger (WPF-Technology - Hardwareaccelerated)
Internet Explorer 9 Beta (Hardwareaccelerated)
Visualiser in Windows Mediaplayer
Terratec Home Cinema (To watch TV with my DVB-S-Card)

More information:
it is only the content of the window that freezes. The border of the windows is still doing everything it should do (i.e. it flashes if a contact of my Live Messenger writes me a new message).
This problem occurs also in a complete new installation of Windows 7 (I allready reinstalled it, because this issue is really ***).
I occurs in the 5.5 and the 5.6 Beta.
I thing the first time I recognized this issue was in the middle of december, maybe a little bit later.

Here is a dxdiag-report:
Operating System: Windows 7 Ultimate 64-bit (6.1, Build 7600) (7600.win7_gdr.100618-1621)
Language: German (Regional Setting: German)
Processor: Intel(R) Core(TM)2 Quad CPU Q9550 @ 2.83GHz (4 CPUs), ~2.8GHz
Memory: 8192MB RAM
Available OS Memory: 8192MB RAM
Page File: 2593MB used, 13787MB available
Windows Dir: C:\Windows
DirectX Version: DirectX 11

I have a ATI Radeon HD 4800 Series and a Samsung Ubisync7 (was bundled with SyncMaster 2263DX) AND a WS Tech USB-DVI Adapter
All in one: 2 "native" displays and 2 displays connected via USB