Turn off after inactivity?

Absolutely! It appears you don't haven't adjusted the "Turn Off After..." setting.

To do this:

1) Double tap your Home button to bring up the Guide.

2) Scroll down to Settings. Select All Settings.

3) Select Power. Under Turn off or restart, you will see "Turn Off After" - This allows you to set your console to turn off automatically when not being used. Your options are 1 hour of inactivity, 6 hours of inactivity or Don't turn off automatically. Select
the "Don't turn off automatically" and that will keep your console on even when you are inactive for extended periods of time.

~Blitz

Right it started doing it again , so should i turn instant on off and my console turns off after 6 hours of inactivity ?

i have with no kinect and doesn't work

I have been in contact with Xbox Support and they are suggesting that running the TV app in full screen is making the XboxOne consider that activity and therefore it'll never turn off... despite whether it's actually receiving a signal or not (my TiVo shuts
itself off after 4 hours). Doesn't seem much use for an entertainment centre to never turn itself off when you're using the TV app even if no TV signal is being received. It should really look for button presses or if the controller hasn't been connected for
a period of time then it's likely the XboxOne could shut itself down. I might try tonight putting the XboxOne to Home and switching to another source to see whether it's off by morning. If it is then it's unlikely I'll be using the Xbox to watch TV anymore.

The Ambassador I chatted with had me do this:

1. Hold the Xbox logo on the console for 10 sec

2. Press the xbox logo once to turn the xbox back on. This cleared the cache

3. Go back to setting and change it to 1 hour if not already and see if that works.

If that doesn't work try changing the power mode to energy savings and see. I don't know if this will actually work but thats what they told me to try. Worth a shot to see if that fixes the problem. I have shut down my xbox several times since friday but
I would like to wake up in the morning and see my xbox turned off. The ambassador also said if this didn't work to came back and tell support that we already cleared cache and tried both power modes. Hope this works for both of us and anyone else who has this
problem.