Can I have you test with the program "xev"?
Run the program in a terminal. Press your brightness-up and brightness-down button should produce some keypressed/keyreleased events on the screen. Please attach the output from the terminal.
Can I have you test with the program "xev"?
Run the program in a terminal. Press your brightness-up and brightness-down button should produce some keypressed/ keyreleased events on the screen. Please attach the output from the terminal.