I'm trying to set some keyboard shortcuts to use single non-standard keys on the keyboard that I don't ever use. Specifically, on my keyboard I have three keys for audio control. I am able to go to Settings > Keyboard shortcuts > and press the corresponding key to set the shortcut, but when I try to use that key it doesn't work.
Keyboard shortcuts calls these keys "Audio previous", "Audio play", and "Audio next". But when I press any of these, even when no shortcut is set on them, I get a square overlay in the lower middle of my screen with a circle with a diagonal line through it. I think this means that some lower level process is intercepting this key like it would with other special keys like screen brightness or volume and is rejected it because there is no audio to deal with, but it is also not passing it on to the system so my shortcut key can use it.
How can I find and disable this so my shortcut will work?
Update: I'm using GNOME and stock Ubuntu 21.10
Several of these keys are defined as media keys. These appear to take precedence over shortcut keys defined in "Settings" - "Keyboard".
You will need to remove their definition under
/org/gnome/settings-daemon/plugins/media-keys/before you can use these keys for something else. You can use dconf-editor for this.For example, following command reveals the keyboard combinations attached to "Audio next":
Use dconf-editor to delete these values, or use the command:
You need to log out then back in for the change to take effect.