The is a 4k Minix box which can send 4k videos, but not Youtube 4k. It seems related to the Youtube app. If I use the smart TV app, it plays 4k, but if I use the official YT app in the box, HD is the maximum resolution shown for 4k videos.
It looks like a Youtube restriction and I don't know of other apps. Playing videos through the YouTube web works but turns out to be cumbersome and impractical.
Any help?
Thanks.
my guess is your box doesn't support a drm level Youtube is looking for - that is why most generic Android boxes won't do 4k in Netflix and I'm guessing here that Youtube has a similar requirement for drm (digital rights management video codecs) I'd start by looking at what Youtube lists vs what your box has for drm levels.