Outcome

Apple TV has HDMI CEC enabled by default. CEC is a control protocol that can interfere with other devices, causing seemingly random behavior on other devices such as unexpected power on or off.

Quick Steps

1. On the Apple TV, go to:
   1. Settings
   2. Remotes and Devices
   3. Control TVs and Receivers
2. Ensure Control TVs and Receivers is disabled (Off).