You can find instructions here.

I just did it, it worked fine. The Bluetooth always on should be disabled. Not sure it actually reset my settings.

My sound bar has been turning itself off or something. When watching TV, it goes black, once when it went black I checked the sound bar, and the lights were off. The Apple TV is plugged into the sound bar. But it could be the 4k HDMI switch causing issues. Or the Apple TV itself.

The last step is wrong, says it’ll say “1 dot 2 dot 0 dot 5”, the page clearly says the newest firmware is 1.2.0.6, and that’s what my sound bar said. I wonder what the older firmware updates did.

Did it fix HDMI CEC? With that enabled, my sound bar keeps changing the input, from HDMI IN to HDMI Arc. You can’t watch anything, as it just keeps changing the input back and fourth.