LG Ultrafine Brightness Dimmed when wake from sleep

I have the exact same setup and the result is the same.

I also have issues with gesture controls using the Magic Mouse with my MBP 16 M1 Pro. After waking from sleep or a screen saver, I sometimes loose gesture controls on the mouse. I either have to log out and log back in to regain, or if you wait until a new screen saver or sleep it sometimes fixes itself.

Lastly, I am also using an external audio interface plugged in one of the LG Ultrafine 5k Displays and after sleep the audio gets pops and cracks (especially YouTube on Safari). I use a tip from another post to temporarily stop this: run an audio file on loop in QuickTime with the audio turned down completely... Hope Apple doesn't take too long to address all of these.

I ran the 12.4 update today too, but it didn't fix the issue with my 27" LG Ultrafine 5K. Looks like I need to send Apple another bug report. Because, you know, that's fun.

I have my display set to auto brightness and that appears to work to keep the display at the brighter level but I do not use sleep and only turn display off after xxx minutes.

A related irritation is the lack of screen-brightness controls on Logitech keyboards, so I have to keep going into preferences to readjust the brightness. May have to capitulate and by a Magic Keyboard.

I can't believe this is still such a mess.

Considering the LG Ultrafine is technically an LG branded Apple product I would expect better support. I have to lower/raise the brightness on mine about 8 times per day since I have to step away from my computer quite a few times during work hours.

I discovered the LG Screen Manager app last week in the Mac App Store so I launched it and had it check for the latest software for the LG 27MD5KL. It tells me the monitor is running the latest version . And yet, the monitor still dims after waking from sleep or screensaver mode. Go configure.

I've also noticed that my MBP 16" M1 Max rearranges floating palettes and open document windows in Adobe apps like InDesign, Illustrator, Photoshop, etc. That's fun.

If I follow the link you provided and search for model 27MD5KL-B I see these items:

[Mac OS] OnScreen Control - version 5.26

Software Guide (Windows, Mac)

[Windows] OnScreen Control - version 7.24

[Mac] LG Screen Manager

Nowhere on there does it have firmware. What is the version of the firmware you downloaded? Unless you're talking about OnScreen Control... which is an application, not firmware.

I'm having the same issue with the following configuration:

Mac Studio M1 Max

MacOS Monterey 12.3.1

Dual LG 4K Ultrafine Displays

Upon wakeup after sleep, the brightness is dimmed. I need to bring both displays back to full brightness manually. PITA.

Actually, I lied. It was behaving but now it's back. Really lame, considering how much these displays cost, even used. I was happy to pay more for the "tight integration" and we get this bull instead. Really disappointing.

Same issue here with a 16" M1 MacBook Pro and a 27" LG Ultrafine 5K

I hadn't noticed this. That's much easier that jumping into preferences every time. Thanks :)

Unfortunately, macOS Monterey 12.2 update didn't fix any of the issues (screen brightness, gesture controls, sound clipping).

I am having the same issue with my 2 LG 5K monitors connected with the new MacBook Pro 14" with M1 max. Every time it comes out of sleep I am having to mess with the brightness. It is so frustrating!

Also having this problem with the LG 5K monitor and 16" M1 Max. It was never an issue with my prvious Intel-based MacBooks and would love to see a fix.

12.2.1 hasn't fixed the issue :(