[GH-ISSUE #1636] My Apple Thunderbolt display is stuck at 30% brightness after using it. #911

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opened 2026-05-05 06:51:44 -06:00 by gitea-mirror · 1 comment

gitea-mirror commented

2026-05-05 06:51:44 -06:00

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Originally created by @Mtkhan13 on GitHub (Oct 2, 2024).
Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/1636

Before opening the issue, have you...?

Searched for existing issues
Read through the Monitor-Troubleshooting Wiki
Updated MonitorControl to the latest version (if applicable)

Describe the issue

I have used this latest app on my mackintosh with Apple Thunderbolt display. But now the brightness is stuck at 30% it doesn't go up-to 100% even the app controls are at 100%. Please let me know what is the problem and how can I fix it.
Thanks

Expected behavior

At 100% range the brightness should be 100% but not 30%.

Anything else?

https://github.com/MonitorControl/MonitorControl/discussions/739 I have read this comment as well its says, it can be change in the code to 250 and that works fine. But I tried downloading few builds but I'm getting so many error while running the code.

Environment Information (please complete the following information)

- macOS version: 11.7.10
- Mac model: Hackintosh iMac Mid 2015
- MonitorControl version: 4.3.2
- Monitor(s): Apple Thunderbolt Display 27"
- Monitor Cable(s)/Connection(s): iMac (HP Thunderbolt 2 Pcie) -> Thunderbolt 2 -> Apple thunderbolt Display 27"
- Apple Silicon/M1 (yes or no): No

Originally created by @Mtkhan13 on GitHub (Oct 2, 2024). Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/1636 ### Before opening the issue, have you...? - [X] Searched for existing issues - [X] Read through [the Monitor-Troubleshooting Wiki](https://github.com/MonitorControl/MonitorControl/wiki/Monitor-Troubleshooting) - [X] Updated MonitorControl to the latest version (if applicable) ### Describe the issue I have used this latest app on my mackintosh with Apple Thunderbolt display. But now the brightness is stuck at 30% it doesn't go up-to 100% even the app controls are at 100%. Please let me know what is the problem and how can I fix it. Thanks ### Expected behavior At 100% range the brightness should be 100% but not 30%. ### Anything else? https://github.com/MonitorControl/MonitorControl/discussions/739 I have read this comment as well its says, it can be change in the code to 250 and that works fine. But I tried downloading few builds but I'm getting so many error while running the code. ![image](https://github.com/user-attachments/assets/b141587e-8a26-407d-80cc-575a6eb1c844) ![image](https://github.com/user-attachments/assets/13681985-05c4-40e8-b4ed-2d811363d80e) ### Environment Information (please complete the following information) ```markdown - macOS version: 11.7.10 - Mac model: Hackintosh iMac Mid 2015 - MonitorControl version: 4.3.2 - Monitor(s): Apple Thunderbolt Display 27" - Monitor Cable(s)/Connection(s): iMac (HP Thunderbolt 2 Pcie) -> Thunderbolt 2 -> Apple thunderbolt Display 27" - Apple Silicon/M1 (yes or no): No ```

gitea-mirror closed this issue

2026-05-05 06:51:46 -06:00

gitea-mirror commented

2026-05-05 06:51:50 -06:00

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@waydabber commented on GitHub (Oct 3, 2024):

Hmm. Not sure why are you trying to recompile the app. Simply go to Settings/Displays/Show advanced (bottom) and set DDC max to 255.

@waydabber commented on GitHub (Oct 3, 2024): Hmm. Not sure why are you trying to recompile the app. Simply go to Settings/Displays/Show advanced (bottom) and set DDC max to 255.