As someone that used to work on a TV app I wasn't surprised when focus issues were the first thing mentioned. It sounds trivial but it takes a surprising amount of testing and bug fixing to get it right.
I remember one time there was a random Philips TV that just kept crashing when the user tried to do "right" on the last item in a horizontal menu. The client kept testing on this TV, and we spent 3 weeks because my team lead at the time wouldn't trust me that I needed the TV to solve it.
They finally agreed to send us the TV. Solved the issue in 10mins.
I remember one time there was a random Philips TV that just kept crashing when the user tried to do "right" on the last item in a horizontal menu. The client kept testing on this TV, and we spent 3 weeks because my team lead at the time wouldn't trust me that I needed the TV to solve it.
They finally agreed to send us the TV. Solved the issue in 10mins.