Problem with volume

[Ocellus]

Hi guys,
I've recently encountered this problem while using Windows 10.
That problem being that turning the volume up or down has no effect, it stays at the exact same volume.
The headphones work fine on my ipod and electric piano.
I can still adjust the volume in videos or on Itunes.
But it doesn't change anymore when using FN + f3. (It used to work just fine)
I tried googling but I didn't really find anything in particular.
Does anyone have a way to fix this?
Thanks in advance.

 

[popatim]

Is this a laptop or special keybd?
Default for Win10 is just F7 & F8, isn't it?

 

[Ocellus]

Is this a laptop or special keybd?
Default for Win10 is just F7 & F8, isn't it?

It's a gaming desktop with gaming keyboard, the buttons on the keyboard aren't the problem though, I can use the buttons to heighten or lower the volume, the sound just doesn't change in volume.