If I make a clean install of windows 7 - fully updated via microsoft update - without Intel's Graphics / HDMI audio drivers - and just use Microsofts generic drivers I can play the files!
By using the generic drives, I can't play HD formats like DTS-HD.
By the way it would not make much sense to play the files without the AVR ;-)
I have downloaded and installed the latest BIOS: from the web site (date 09-19-2014) I think that is the one you refer to?
Units for sound and video:
Intel(R) Corporation
09-09-2014
Version: 6.16.0.3154
Gfx:
Intel Corporation
30-09-2014 (09-30-2014)
version: 10.18.10.3958