[audit13]

I deeply apologize, if this has been previously discussed, but I haven't been able to find any relevant answer so far.

I don't have 4k resolution available in the whitelist, only 1920x1080 with different refresh rates. Why is that?

Same situation here... But I don´t know why.
Any ideas?

I have the same issue and it's something I can live with because I set the mi box 3 output resolution to 1080p60 in the Android settings. When I play a 4k 2160p file, the resolution changes to 2160p at 23.98 and goes back to 1080 when I close Kodi. I only use the mi box for playback of content from a usb drive because Netflix, Vudu, and Google Play movies look far better from my Apple tv 4k or the LG TV app.