I'm am running 6.0 and the mi box when sent a YouTube cast opens the YouTube app and just shows a black screen which is one that youll see when you first play a YouTube video.
Any ideas?
I loved the idea of using it as a lite Netflix, crunchyroll box with casting abilities but now I'm not so sure
Reboot everything. Phone, mi box, router. Try again.
Don't update to 7 or your mibox will be broken.
A workaround would be to link it the YouTube app. That way you'll just have to fire up YouTube on mibox once and you can then control everything from your phone.
I have this problem too sometimes. Just stop casting then cast again once or twice and it'll work.
update mi box and it will work normally