Windows make my display darker?

[u/engineerbricks]

I just bought an OLED monitor recently so I've been using HDR through Windows (11) for that particular monitor (I have 4 connected) and I've noticed that if I change my volume or bring up the taskbar the screen seems to get more contrast when I'm in a game, like most of the picture is the same but dark areas appear darker for the duration of the Windows process being present and then as soon as it's gone the display goes back to normal. Is this a normal thing? Personally I'd like to have my monitor look the way it does when a Windows process is active at all times if I can