I updated 2nd slot to see if that helped.. Didn't.. But I figured out why.. Not sure why but the awesome DE-Throttling mod the guy from other thread created was causing the problem..for me anyway. I deactivated that and power button is back to normal.Sorry to hear that, I can remember a while back on the 8 pro and a few Pixels, it seemed like every time or just about every time I updated, I'd have to wipe my device for one reason or another. Now if that doesn't fix it then I guess it would be custom ROM time.