[GH-ISSUE #796] Volume mapped to contrast for my Display? #512

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opened 2026-05-05 06:10:02 -06:00 by gitea-mirror · 2 comments

gitea-mirror commented

2026-05-05 06:10:02 -06:00

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Originally created by @robcalcroft on GitHub (Nov 18, 2021).
Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/796

Originally assigned to: @waydabber on GitHub.

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

Volume doesn't work and appears in some cases to be mapped to contrast instead, i have tried the https://github.com/MonitorControl/MonitorControl/wiki/Monitor-Troubleshooting#try-a-different-ddc-tool tool and brightness works but volume doesn't. There are no errors shown and the app appears to think it can control volume and the keys respond correctly but i dont hear a change in volume.

Expected behavior

Volume should change on pressing hardware buttons or changing slider in MonitorControl interface

Anything else?

No response

Environment Information (please complete the following information)

- macOS version: 11.6.1
- Mac model: MacBook Pro (16-inch, 2019)
- MonitorControl version: 4.0.1
- Monitor(s): MSI Optix MAG342CQRV
- Monitor Cable(s)/Connection(s): USB-C to https://www.amazon.co.uk/gp/product/B08H5CYC43/ref=ppx_yo_dt_b_asin_title_o01_s01?ie=UTF8&psc=1 to Monitor
- Apple Silicon/M1 (yes or no): no

Originally created by @robcalcroft on GitHub (Nov 18, 2021). Original GitHub issue: https://github.com/MonitorControl/MonitorControl/issues/796 Originally assigned to: @waydabber on GitHub. ### 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 Volume doesn't work and appears in some cases to be mapped to contrast instead, i have tried the https://github.com/MonitorControl/MonitorControl/wiki/Monitor-Troubleshooting#try-a-different-ddc-tool tool and brightness works but volume doesn't. There are no errors shown and the app appears to think it can control volume and the keys respond correctly but i dont hear a change in volume. ### Expected behavior Volume should change on pressing hardware buttons or changing slider in MonitorControl interface ### Anything else? _No response_ ### Environment Information (please complete the following information) ```markdown - macOS version: 11.6.1 - Mac model: MacBook Pro (16-inch, 2019) - MonitorControl version: 4.0.1 - Monitor(s): MSI Optix MAG342CQRV - Monitor Cable(s)/Connection(s): USB-C to https://www.amazon.co.uk/gp/product/B08H5CYC43/ref=ppx_yo_dt_b_asin_title_o01_s01?ie=UTF8&psc=1 to Monitor - Apple Silicon/M1 (yes or no): no ```

gitea-mirror

2026-05-05 06:10:02 -06:00

closed this issue
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gitea-mirror commented

2026-05-05 06:10:06 -06:00

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@waydabber commented on GitHub (Nov 18, 2021):

This seems to be a monitor specific issue. It might be that the display's firmware incorrectly maps the volume command to brightness.

I'd advise you to go to Displays, enable Show advanced settings and try changing the VCP value for the volume command to something that the display accepts as volume control code.

You can see the control codes according to the standard here but not all displays follow the specification:

https://github.com/MonitorControl/MonitorControl/blob/master/MonitorControl/Enums/Command.swift

so for example volume is set by audioSpeakerVolume which has a control code of 62 by default. Try using a different number from the list until you find one that might work (you might want to try contrast which is 12, maybe these are reversed in the firmware).

@waydabber commented on GitHub (Nov 18, 2021): This seems to be a monitor specific issue. It might be that the display's firmware incorrectly maps the volume command to brightness. I'd advise you to go to Displays, enable `Show advanced settings` and try changing the VCP value for the volume command to something that the display accepts as volume control code. You can see the control codes according to the standard here but not all displays follow the specification: https://github.com/MonitorControl/MonitorControl/blob/master/MonitorControl/Enums/Command.swift so for example volume is set by `audioSpeakerVolume` which has a control code of `62` by default. Try using a different number from the list until you find one that might work (you might want to try `contrast` which is `12`, maybe these are reversed in the firmware). <img width="842" alt="Screen Shot 2021-11-18 at 19 20 37" src="https://user-images.githubusercontent.com/37590873/142473925-7e896f33-dd12-4d02-92c5-85a754d118a5.png">

gitea-mirror commented

2026-05-05 06:10:07 -06:00

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@waydabber commented on GitHub (Nov 18, 2021):

(I'll move this over to discussions, we can continue there).

@waydabber commented on GitHub (Nov 18, 2021): (I'll move this over to discussions, we can continue there).