I have an acer aspire 5517, and the fn+up does not change the volume but the fn+left key changes brightness. Also the fn+f11/f12 keys do not skip songs. Right now I have to enable Gnome Services to get this to work. I am wondering if it works in Gnome why does it not work in XFCE.
*** This bug has been marked as a duplicate of bug 8588 ***