New Studio Display Brightness Problem

I had the same problem.

I disconnected the display and updated to 12.3. Everything works now.

Also install the 600mb display firmware update after you update macos to 12.3

I have a 2017 15" MacBook Pro, all up to date with macOS 12.3 and current 15.4 firmware. I cannot adjust the brightness of my connected Studio Display in any other color mode than Apple Display (P3-600 nits). I'm a designer and I work in sRGB. Called customer support and they told me it won't be fixed without a firmware or OS update. Really hoping they fix this issue because I really don't want to have to return this display. Huge deal breaker if I can't adjust the brightness of my screen though.

My mind is blown that this is the way it works for something marketed towards designers.

following

Did you find any solution?

Please let me know if you find one.

I would suggest ensuring you're on the latest version of MacOS on your 16" MacBook Pro (which is required to properly use the monitor). Also, if you have any updates in system preferences on your Mac for your display, install those as well.

Set up and use Apple Studio Display - Apple Support

Update macOS on Mac - Apple Support