Question: why did tv suddenly display an airplay code?
I was watching TV, not through Apple TV although it was on. Suddenly, the program I was watching on broadcast station disappeared and the TV screen said iPhone Air Play Code and a 4 digit code. After several minutes, that disappeared and the regular TV program returned. I have no idea what caused that, and looking all around at my iPhone, my Mac, etc. doesn't give me a clue.
Apple TV (4th generation), tvOS 11