Toshiba Satellite model L55-A5226, W10 Anniversary Home.
For a while now the sound volume keys don't work at all, neither does mute. I know I can adjust sound other ways, but I like the convenience of using the keys. There have been no recent updates that I'm aware of or anything new that may have caused this.
Go to the Toshiba support site and download and install the relevant Toshiba Windows 10 'System Driver' 'System Settings' and 'Function Key' applications. The latter should make an appearance in the Start-up Tab of the Task Manager.
I used to have that problem with Windows 8.1 of the Special function keys sometimes stopping working, in that case going to the Desktop Assist and the System settings > Function Key application would restart the special functions.
However since Windows 10 no problems.
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