(2015-08-20, 07:34)fritsch Wrote: Yeah - no dear windows users, please stand up and go to the intel support forum and tell them to fix this. I would never accept it as a user - that a single, damn driver destroys my home theater experience cause of some stupid political reasons.
Political or I'd rather say commercial. It's often the case with different products that certain features are only limited with software in order to achieve product differentiation. As an example, cars are sold with the exact same engine, but on the cheaper model it's limited with software on to a certain level.
However, what seems to be baffling is that on the Intel support forums Intel guys themselves have not been able to answer if the Windows drivers actually support HD Audio passthrough. Some of them have asked users to go through all kind of hoops in order to get things working. In other words, they don't seem to know themselves.
I noticed that in the HD Graphics driver package on the Intel support site (I downloaded version 15.40.3.64.4248) there's directory DisplayAudio that contains two different versions of HDMI Display Audio driver: 6.16.00.3178 and 8.20.00.500. The latter will be installed for device VEN_8086&DEV_2809 whereas the former applies for devices VEN_8086&DEV_2807, VEN_8086&DEV_2808 and VEN_8086&DEV_2883. I noticed that my Braswell NUC was VEN_8086&DEV_2883. The same HD Graphics driver applies for Broadwell and Braswell NUCs. Broadwell supports HD Audio passthrough.
Thus I wanted to know if the driver with version number 8.20.00.500 would be the full-featured driver and the other the limited driver. I modified the inf file in the 8.20.00.500 directory to contain DEV_2883 instead of DEV_2809 (you need to change it on two lines quite in the beginning of the file). Then I went to device manager, updated the driver for the "Intel® Display Audio" using the "Have disk" method and pointed to the 8.20.00.500 directory. However, I got an error about unsigned driver and the attempt failed. By following the approach described
here I was able to install the driver.
Now the problem is that I don't have a device that would support HD Audio Passthrough. I can see (hear) that the audio via my TV works, so it did not break it totally. But it could be nice if someone with a passthrough capable receiver would try this and report the result here.