I finally got a reply from 'ATI customer support' which I had to post below as it doesn't even relates to the product I was talking about. I'm really angry now because they make you buy a very expensive graphics card which claims to accelerate blu-ray playback but then doesn't even play any disc let alone accelerate anything - and if you contact their support team they send you one standard reply after another without addressing the problem - maybe it wasn't such a good idea relying on the ATI card to start with...
ORIGINAL REPLY FROM ATI CUSTOMER SERVICE:
Thank you for contacting AMD Global Customer Care for ATI Products.
In order to address your issue, we highly recommend that you have installed all the required updates (hotfixes) for MS Windows Vista.
NOTE: Please install these updates manually since these are not included in the automatic updates that you receive.
a) 737-30139: Microsoft Windows Vista Hotfixes for all RadeonT users
The Microsoft hotfixes that are listed below are recommended for people using a RadeonT based graphics card in Windows Vista.
Compatibility and Reliability:
http://support.microsoft.com/kb/938194
Performance and Reliability:
http://support.microsoft.com/kb/938979
DirectX 10 and Crossfire patch:
http://support.microsoft.com/kb/936710
Virtual Address Space Usage in Windows game development patch:
http://support.microsoft.com/kb/940105
The information in this article applies to the following configuration(s):
• RadeonT HD2900 series
• RadeonT HD2600 series
• RadeonT HD2400 series
• RadeonT X1950 series
• RadeonT X1900 series
• RadeonT X1800 series
• RadeonT X1650 series
• RadeonT X1600 series
• RadeonT X1550 series
• RadeonT X1300 series
• RadeonT X1050 series
• RadeonT X850 series
• RadeonT X800 series
• RadeonT X700 series
• RadeonT X600 series
• RadeonT X550 series
• RadeonT X300 series
• RadeonT 9800 series
• RadeonT 9700 series
• RadeonT 9650 series
• RadeonT 9600 series
• RadeonT 9550 series
• RadeonT 9500 series
• Windows Vista 32-bit Edition
• Windows Vista 64-bit Edition
Solution:
Make sure your PC is configured to install all Microsoft Vista updates available through Windows Update automatically.
Download and install the hotfixes listed at the top of this article (which are not available through Windows Update).
In addition, please ensure that you confirm that you system is compatible with MS Windows Vista - see the MS Windows Vista Hardware Compatiblity List.
https://winqual.microsoft.com/hcl/ (requires Internet Explorer 6 or higher)
Finally, ensure that you have updated your motherboard BIOS and chipset drivers (if available).
In you still experience these issues, please submit your comments through the Catalyst Crew Feedback Form for immediate consideration of your driver and software related issues for inclusion in future driver releases:
Catalyst Crew Feedback Form:
http://support.ati.com/ics/survey/survey.asp?deptID=894&surveyID=486&type=web