then my samsung TV in my bed room simply interpets the request differently than my samsung TV in my living room?
Yes, apparently. Possibly the difference is in Settings on Apple TV, on the TV, or both.
I have a samsung the frame and Apple TV 4K in my bed room and my living room. The difference is that I have a Sonos Beam connected as well in my living room.
My point was, that a third device does not make a difference for turning off (setting to standby of) the TV.
Are both TVs the same model?
I guess I need to purchase some kind of receiver?
No, that is not needed for CEC/turning off|on connected devices.
- Turn on CEC on Apple TV:
Settings﹥Remotes and Devices﹥Control TVs and Receivers﹥On
- Turn on CEC on your TV:
Home button﹥Settings﹥System﹥Expert Settings﹥Anynet+ (HDMI-CEC)﹥On
or: Home button﹥Settings (All Settings)﹥General (Connection)﹥External Device Manager﹥Anynet+ (HDMI-CEC)﹥On
(Exact menu navigation may differ by model TV and version OS of the TV. See your TV manual if needed.)
- That is all you can do. If it doesn’t work with those settings, then consult with Samsung Support.
Use Anynet+ on your TV - Samsung Support