ATV2 turns on by itself?

It's likely picking up on network activity. Set the sleep to never

I don't know if this is the same issue but since I got the ATV 2 it has intermittently come awake. But not actually awake, that is the light on the front of the device will light up but if I switch my tv to the input that the ATV uses there won't be anything onscreen. I have to click the menu button on the remote for it too actually wake up and then I will see the onscreen options. Before this last update that issue had been corrected and I wouldn't see the light unless I actually used the remote. Now since the latest update the issue is back. If I go to the tv input nothing will be onscreen until I use the remote and I can tab over to the general, sleep now tab, click on that and it does go to sleep with the light off. However after a period of time the light comes on again for no reason that I can figure out. It will stay on until I get the time to go back in and put it to sleep again. I also believe that turning the tv on or off will trigger this as well. When I first got it turning the tv on would always make it do this. But a couple of updates ago that was corrected. Now it's back. I have it set to go to sleep after 15 minutes which it will do if I'm using it.

As far as I am aware the status light on the Apple TV has detected network/HDMI activity with every version of Apple TV software that has been released.

The status light does not necessarily mean the Apple TV is awake.

One of the past updates had corrected that ( or messed it up?? ). I hadn't seen mine do this for a while until the latest update within the last week or so. As you said it's not really awke but it is annoying because that light stays on permanently unless I go in and manually wake it and then put it to sleep again.

The status light does not stay on unless the Apple TV is on. I'd suspect you have issues with either HDMI or your network if the status light is on and the TV has no signal when switched on. I'm also thinking this has something to do with the update you had that changed this behaviour

In the past turning the tv on would activate the status light every time. A few updates ago that stopped happening but occasionally I would see it activate for no apparent reason and then it would go out. I just figured it was "phoning home" or checking for an update. Before this latest update that had stopped also. Now afterwards it's doing it again but it's erratic. I just tried turning the tv off for a few minutes then turned it back on but nothing happened. So there's no pattern to this that I can detect but when the light does activate for whatever reason, it does not go out until I manually go in wake it up then put it to sleep again. Seeing these other recent posts lead me to believe others are seeing the same issue. The updates may be having slightly different effects on each device. As I said one of the previous updates had corrected this for me and the latest has returned it.

Thank you so much for your post. I appreciate the confirmation that it is happening to other devices.

Same problem here running 4.4. I have 2 ATV2's, and it only seems to happen to one of them. The one it happens to is connected to an older TV, so I wonder if it is an HDMI issue of some sort. If I really get sick of it, maybe I'll switch them and see what happens.