Solved! Acer key

[JLA]

Hello,
the f8 button don't mute the volume. Why don't it work?
for the acer

 

[CaedenV]

there is a Fn (function) button (near alt/ctrl on the left side) that you need to press allong with f8 to get the functions to work. Otherwise you are just pressing f8, which likely has no meaning in the context of whatever software you were running