I have the NUC5i7RYH and just installed Build 10162 from scratch. After installation, the speaker icon in the taskbar was red-crossed out indicating no speaker, and Device Manager complained about an SM Bus Controller. Note that I'm using the mini-DP port for video/audio.
- Download RYH-RYK-Win8.1-64bit-Driver-Bundle-Jul2015.zip and unzip it.
- Navigate to the Chipset folder and unzip Chipset_Win7_8_8.1_10.0.27.zip
- Navigate to SetupChipset.exe and run it.
- Voila, that takes care of the SM Bis Controller.
- Go back to the root folder and navigate to the Graphics folder and unzip GFX_Win7_8.1_64_18.104.22.16822.zip
- Navigate to the DisplayAudio folder.
- Right-Click on IntcDAud.inf and select Install.
- Voila, sound works!
No more problems have been experienced. I think this solution works.