[GH-ISSUE #1083] The brightness is not controlled properly when it is higher than 50%. The device randomly crashes when adjusting the brightness. #643

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opened 2026-05-05 06:26:14 -06:00 by gitea-mirror · 2 comments

gitea-mirror commented

2026-05-05 06:26:14 -06:00

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Originally created by @dev-coco on GitHub (Jun 16, 2022).
Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/1083

Before opening the issue, have you...?

Searched for existing issues
Looked through the wiki
Updated MonitorControl to the latest version (if applicable)

Describe the bug

The brightness control bar does not control the brightness properly. The brightness will be reduced only when the brightness is below 50%, and there will be no change in adjusting the brightness between 50% ~ 100%.
When adjusting the brightness, there is a probability that the display will crash, but so far I have not found any law to reproduce, it seems to be a random occurrence. I had to reboot the device to get it back to normal.

I am not sure if I have described it clearly, if necessary please leave your email and I can send a video demonstrating the bug.

Steps to reproduce

Use the reduce brightness button on the keyboard to reduce the brightness
Reduce the brightness only when the brightness is reduced below 50%, and it has no effect when it is between 50% ~ 100%.

Expected behavior

Any range between 0% ~ 100% should take effect normally.

Anything else?

This bug was found in MonitorControl v4.1.0, I tried v4.0.2 and v4.0.1 both are working fine.

Environment Information (please complete the following information)

- macOS version: 12.3.1 Monterey
- Mac model: Mac mini (M1, 2020)
- MonitorControl version: v4.1.0
- Monitor(s): LG HDR 4K
- Apple Silicon/M1 (yes or no): yes

Originally created by @dev-coco on GitHub (Jun 16, 2022). Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/1083 ### Before opening the issue, have you...? - [X] Searched for existing issues - [X] Looked through [the wiki](https://github.com/MonitorControl/MonitorControl/wiki) - [X] Updated MonitorControl to the latest version (if applicable) ### Describe the bug 1. The brightness control bar does not control the brightness properly. The brightness will be reduced only when the brightness is below 50%, and there will be no change in adjusting the brightness between 50% ~ 100%. 2. When adjusting the brightness, there is a probability that the display will crash, but so far I have not found any law to reproduce, it seems to be a random occurrence. I had to reboot the device to get it back to normal. I am not sure if I have described it clearly, if necessary please leave your email and I can send a video demonstrating the bug. ### Steps to reproduce 1. Use the reduce brightness button on the keyboard to reduce the brightness 2. Reduce the brightness only when the brightness is reduced below 50%, and it has no effect when it is between 50% ~ 100%. ### Expected behavior Any range between 0% ~ 100% should take effect normally. ### Anything else? This bug was found in MonitorControl v4.1.0, I tried v4.0.2 and v4.0.1 both are working fine. ### Environment Information (please complete the following information) ```markdown - macOS version: 12.3.1 Monterey - Mac model: Mac mini (M1, 2020) - MonitorControl version: v4.1.0 - Monitor(s): LG HDR 4K - Apple Silicon/M1 (yes or no): yes ```

gitea-mirror

2026-05-05 06:26:14 -06:00

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gitea-mirror commented

2026-05-05 06:26:20 -06:00

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@waydabber commented on GitHub (Jun 16, 2022):

Hi, the app uses a combined brightness control approach by default. Between 0-50% the dimming is achieved via software means and beyond 50% there is hardware backlight control. If this part of the scale does not work then for some reason DDC control fails.

Can you an alternative app like BetterDisplay and see if control works properly?

@waydabber commented on GitHub (Jun 16, 2022): Hi, the app uses a combined brightness control approach by default. Between 0-50% the dimming is achieved via software means and beyond 50% there is hardware backlight control. If this part of the scale does not work then for some reason DDC control fails. Can you an alternative app like [BetterDisplay](https://github.com/waydabber/BetterDummy) and see if control works properly?

gitea-mirror commented

2026-05-05 06:26:21 -06:00

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@waydabber commented on GitHub (Jun 16, 2022):

Ohh but I see you did run v4.0.2 earlier with no problem. The issue most probably is that you are using HDMI connection which blocks hardware backlight control. You'd need to use the USB-C port of your Mini to connect the display for that. MC 4.1.0 had a check removed that blacklisted the HDMI port of various M1 devices (this is because many models are out now with differing service ports for HDMI and a blanket ban would also blacklist USB-C to HDMI dongles, most of which would work otherwise). If you want to fix this by using software control only, navigate to the Displays section of MonitorControl and disable DDC for the display.

Hope this helps!

@waydabber commented on GitHub (Jun 16, 2022): Ohh but I see you did run v4.0.2 earlier with no problem. The issue most probably is that you are using HDMI connection which blocks hardware backlight control. You'd need to use the USB-C port of your Mini to connect the display for that. MC 4.1.0 had a check removed that blacklisted the HDMI port of various M1 devices (this is because many models are out now with differing service ports for HDMI and a blanket ban would also blacklist USB-C to HDMI dongles, most of which would work otherwise). If you want to fix this by using software control only, navigate to the Displays section of MonitorControl and disable DDC for the display. Hope this helps!

gitea-mirror referenced this issue

2026-05-05 07:06:02 -06:00

[PR #643] [MERGED] Update Korean Translation #1145