Question about Xiaomi MI TV Stick 4K

Have you tried using the stick with an external power supply instead of the display USB? Maybe your stick is not getting enough power.

Hm, I have 2 sticks and 1 box from xiaomi and none of them are acting up, except for one app that goes crazy, but that's not xiaomi's fault...

Basically, the devices must be connected via the external charger, USB from the TV is not enough, as it can lead to malfunctions.
So if you are already using the external charger and the HDMI cable supplied, then only the stick can be faulty!
Otherwise, test it again on another TV! I can't really imagine that it's due to a setting on the previous TV. I haven't had any problems with it so far. Connect, set up, done.