I have chosen to use the F1-F12 keys with their original -PC- behavior, because I want F5 to refresh the page in Firefox! (and not control the backlight of the keyboard)
Now I would like to "remap" the Volume Up/Volume Down key as originaly intended: F11 and F12 keys (I'm used to that). I don't want to have to press Fn everytime.
I've searched everywhere I can't find a way to do that (for now I have to press Fn+F11 and Fn+F12).