We received a new AppleTV 4K(Siri capable) unit as a Christmas gift. Since it has been hooked up, we have experienced our TV turning on at random times in the night.

My wife did some internet exploration, what she saw that others have experienced the phenomena, with nothing conclusive about cause.

We may deactivate the Siri and see what that does, since the Apple TV unit doesn't turn off completely, as our older AppleTV unit does with the sleep now command. Anybody else experincing this?

We have the earlier models of Apple TVs but I have heard several people talking about this.

It appears that it is a result of having the Apple TV Siri remote set to turn on your TV (or else CEC being enabled). Exactly WHY the Apple TV isn't remaining in autosleep isn't determined as yet from what I understand.

An intermediate fix is to go into settings - remotes and devices - control tv and toggle off.
I think you can also change this from your actual TV's HDMI-CEC settings.
(Some manufacturers call by different terms). It may be a case of getting things to play together properly.
I'm sure there will be more about it coming out-