[ciscostud]

I am also an early adopter and I have this very same issue where only stereo audio is available via the HDMI port. I tried several different HDMI 2.0 compliant cables just to see if the cable was the culprit but no luck. I have no issues whatsoever with my other older NUC5i7RYH outputting multichannel surround audio via my Denon AVR-S910W receiver. I tried both the latest and the previous released graphics driver, which would contain the Intel Display Audio driver, but still no luck.

I logged a case with Intel over the phone at their support contact number 916-377-7000, option 3. If you are experiencing this same issue, I recommend you join with me in bringing this to Intel's attention. The agent I spoke to had not yet heard about this issue so please do your part and let your voice be heard so this gets high on their priority list.

I am having the EXACT same problem with the Intel Skull Canyon NUC on Windows 10 that both of you describe above. I just received mine yesterday. You may or may not be happy to know that this problem with HDMI 5.1 or multichannel passthrough is effecting both my Yamaha 5600 sound bar and Yamaha 5100 AV Pre-Amp. So it is not just a Denon problem. It is a Yamaha problem too. I hear this may not be happening under Linux. It sounds to me like it is a Windows Driver Issue (Intel Display Audio?). I am also running the latest drivers with the Intel Driver Update Utility. I called this in also to Intel Support and they opened a case with the phone number above.

Cool! I have both a thread on the Intel support forums and a Reddit thread on the Intel NUC subreddit, linked below. Below also is a family member's Amazon review of the product. I will post a link to the fix at Reddit and the Intel support forums as soon as it comes.
https://www.reddit.com/r/intelnuc/commen...work_over/
https://communities.intel.com/thread/102165
http://www.amazon.com/review/R1I49QUJ7M4...6&store=pc

I see Intel on their forum is suggesting you try the display port with an adapter on their new Skull Canyon NUC for 5.1 passthrough. It very well could work, but this is a work around and not a fix. It needs to work on HDMI!!