Got the android 9 update on my xiaomi mibox 3.
It has again the same annoying bugs that plagued the mibox on Android 7, after a few hours the box will freeze and it won't be possible to wake it up anymore, need to reach the back and unplug it
It happened on both my boxes
I feel they just pressed compile and then pushed without testing
Enable developer options, and toggle on the setting to always stay awake. This solved the problem of the MiBox going into permanent sleep for me.
Try resetting if possible multiple times. I don't have these wake bugs nether before or now.
Also turn on CEC, even if you don’t use it. That fixed mine pre update and is still fine post update.
Never had this issue. First check your setup before blaming software
Glad to see Xiaomi finally updated to Android 9. I gave up on that box it was nothing but issues, got the 2017 Shield TV when it was on sale and it's been amazing.
Try this solution for unresponsive remote after sleep:
https://forum.kodi.tv/showthread.php?tid=275083&pid=2982706#pid2982706
Why Google would think any mains electrically powered device needs “Energy Optimisation” crap in their Android OS has me scratching my head ?