I've an ASUS N56JN and brightness shortcut doesn't work. Usually with my laptop I can do it with FN+F5/F6. How can I solve this issue? Is there a way to fix it? Thanks!
Use the instructions on this page, but instead go to
Custom and select the
+ button to add a new keyboard shortcut. In the custom command, put
xdotool key XF86MonBrightnessDown or
xdotool key XF86MonBrightnessUp. Then click where it says
Disabled and key in your key combination.