A/V power options

Do you have an original Xbox One, or a Xbox One S/X? If you have the original Xbox One (not the S or X) you will need to have Kinect in order to have the Xbox control your A/V equipment.

If you do have Kinect and/or a Xbox One S/X, make sure that the IR Blaster on the Kinect and the console aren't obstructed, and that the IR light can hit your equipment. If you have a home theater with dark walls, it might be that the IR signal can't be
reflected off the walls towards the A/V equipment.

And finally: The TV needs to be able to be controlled via Infrared remote controls. If you have a very modern TV with a Bluetooth remote, the Xbox can't control that. It has to be Infrared controlled.

EDIT: You could get an IR extension cable: https://beta.support.xbox.com/help/hardware-network/oneguide-live-tv/use-external-ir-with-xbox-one

Original Post:

The Xbox One S and X models have the Infrared Blaster built in, as Microsoft decided to make Kinect an optional accessory.

Since the original Xbox One initially came bundled with Kinect, the console didn't need an additional IR Blaster built in. The Kinect had an IR emitter already for the depth measuring, so it made sense to put the IR blaster into Kinect.

So without Kinect, the original Xbox One can't control your A/V equipment.

Oh, thank you, noone could answer that before. And as for the Original Xbox One, is Kinect the only way to power my TV on/off automatically?

Bintokin,,

If you go to Settings - Power & startup - TV & A/V power options, do you see multiple options for powering on a and off your tv? "Nothing" is the only option in all of my settings.

Go to Settings, Power & Startup. Click on the TV & A/V power options. I'm guessing the Comcast is set to Toggle. There are two options per device, one for power on,and one for power off. I would set power on to on, and the power off, to off. See if that
stops your problem.