[riccardo]

... I am still having the same issue with my NUC7i3BNH not being able to pass DTS-HD Master or TrueHD. It doesn't matter if I have it at 60p or 24p.
To refresh NUC7i3BNH (Kaby Lake) >HDMI cable >Yamaha A3010 receiver > Epson Projector. 
This receiver projector combo has worked fine for me to stream DTS HD Ma/TrueHD for many years using previous Kodi builds (Chromebox, PC, Dell/Wyse Thin Clients, etc). 
I updated the NUC HDMI firmware to 1.66 some time ago and this NUC box works fine with Windows 10 and official Windows 32 bit Kodi. It passes HD audio and does so with refresh rate switching down to 24p. 
...

 I have similair issues as billbillw on NUC6CAYH+Onkyo TX-SR608. Audio Passthrough works very strange. On LibreElec 8.2.x audio pass works only for non-HD audio formats, eg DD a DTS while formats like DD-EX, DTS-EX, DTS-HD MA5.1/7.1 and Dolby THD 7.1 don't work at all. On these new builds 9.x audio is passed correctly in most cases, but video is not smooth with refresh rate set to 60 Hz (or 59.97). Refresh rates 29.97 and lower give no audio at all for any audio format. I wonder if it's a prolem with NUC6CAYH generally and I need to get myself a newer NUC, but since not so many people complain about this I have a strange feeling that the problem might be somewhere else. I've upgraded HDMI firmware recently to 1.72 without any effect; also read somewhere that a new kernel 4.13+  will fix this. Some progress has been made but it's far from being usable. I still need to transer audio over optical cable and therefore downgrade all the HD audio formats.