I have two Apple TV 4s in my L-shaped studio apartment (one in the "living room" area and one in the "bedroom" area). The remote for each one only controls it's respective ATV4 except that pressing a button on the living room remote also wakes the bedroom ATV4 from sleep. The bedroom ATV4 remote does not wake the living room ATV4. I have conjectured that this is because when I point my living room remote at the living room ATV4, it is in line of sight with the bedroom ATV4. Using the remote in the bedroom is not in line of sight of the living room ATV4 and it does not wake from sleep. I wonder if the ATV4 is using IR to wake the units rather than, or in addition to, bluetooth?