I use NUC6CAYH . Also looked for optical output. I've tried it with AudioQuest cable, but that only supported 24/96. Today i received sysconcept cable and it should do 24/192. I'll try
As for the noise, this is how i did discover it - after a very low level track , when amp volume was at 10-11 o'lock , i could hear it even from 1meter distance from loudspeaker. Then i've disconnected Chord Qutest original PSU, leaving only Naim 5si - no noise. Connected Qutest to Anker Power bank - no noise.
To my surprise - it not only removed noise, sound changed very much. I was astonished by how much . I never believed in PSU upgrade thing. Now i'm starting to...