For years I've had an issue where when I lock my screen and it fades to black on the lockscreen to save power...a good thing. It would wake up ~7s later. This was a constant loop, so I had to turn off my monitors if I was deliberately leaving the computer running something. Today I found out it was because one of my monitors was set to auto for its input. When it had no input it was asking over DisplayPort and HDMI "are you there?". PSA: set your monitor input to a dedicated input source.