[GH-ISSUE #1845] External monitors lose control after adjusting built-in display brightness #1011

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opened 2026-05-05 07:01:40 -06:00 by gitea-mirror · 1 comment

gitea-mirror commented

2026-05-05 07:01:40 -06:00

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Originally created by @mkinkela1 on GitHub (Mar 18, 2026).
Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/1845

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

I'm running into an issue when using MonitorControl with a MacBook and two external monitors connected via USB-C. Whenever I adjust the brightness of the built-in display (using keyboard brightness keys), I’m no longer able to control the external monitors with the same keys. To regain control, I have to open the app and reselect the external displays manually.

Steps to reproduce

Connect 2 external monitors via USB-C
Use brightness keys to adjust external monitors → works fine
Adjust brightness of the built-in Mac display
Try adjusting brightness again → external monitors no longer respond

Expected behavior

Brightness keys should continue to control external monitors (or all displays, depending on settings) without needing to reopen or refocus the app.

Anything else?

No response

Environment Information (please complete the following information)

- macOS version: 26.2 Tahoe
- Mac model: MacBook Pro (16-inch, 2023)
- MonitorControl version: 4.2.0
- Monitor(s): Dell Flat Panel 27" P2722HE with USB-c and RJ45 x2
- Apple Silicon/M1 (yes or no): no

Originally created by @mkinkela1 on GitHub (Mar 18, 2026). Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/1845 ### 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 I'm running into an issue when using MonitorControl with a MacBook and two external monitors connected via USB-C. Whenever I adjust the brightness of the built-in display (using keyboard brightness keys), I’m no longer able to control the external monitors with the same keys. To regain control, I have to open the app and reselect the external displays manually. ### Steps to reproduce 1. Connect 2 external monitors via USB-C 2. Use brightness keys to adjust external monitors → works fine 3. Adjust brightness of the built-in Mac display 4. Try adjusting brightness again → external monitors no longer respond ### Expected behavior Brightness keys should continue to control external monitors (or all displays, depending on settings) without needing to reopen or refocus the app. ### Anything else? _No response_ ### Environment Information (please complete the following information) ```markdown - macOS version: 26.2 Tahoe - Mac model: MacBook Pro (16-inch, 2023) - MonitorControl version: 4.2.0 - Monitor(s): Dell Flat Panel 27" P2722HE with USB-c and RJ45 x2 - Apple Silicon/M1 (yes or no): no ```

gitea-mirror closed this issue

2026-05-05 07:01:43 -06:00

gitea-mirror commented

2026-05-05 07:01:47 -06:00

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@waydabber commented on GitHub (Mar 27, 2026):

Isn't it that MonitorControl simply stops running? The v4.2.0 app version is not compatible with Tahoe and might simply crash when adjusting the built-in display brightness. Try upgrading to the latest app version from the website (auto-update in 4.2.0 no longer works).

@waydabber commented on GitHub (Mar 27, 2026): Isn't it that MonitorControl simply stops running? The v4.2.0 app version is not compatible with Tahoe and might simply crash when adjusting the built-in display brightness. Try upgrading to the latest app version from the website (auto-update in 4.2.0 no longer works).