Keyboard input lag, only gets fixed on restart temporarily

[dniosaur]

HARDWARE:
8gb ram
Logitech mk270r (wireless keyboard & mouse on one usb)

ISSUE:
input lag on keyboard only.
a delay for half a second, doesn't stop and will register everything you press, registers the input even if you exit notepad already.

POSSIBLE CAUSE?:
Probably from using windows key instead of "alt-tabbing" out of a game,
because pressing the windows key opens up the start menu and the taskbar.
I'm not sure tho, I haven't tested it intentionally.
I have read about SuperF4 causing this input lag so will try deleting it.

FIXES I TRIED:
-a restart fixes it temporarily
-changing the batteries
-changing usb port
-using other keyboards
-turned off filter keys

It works perfectly like a proper keyboard when you go back in game and only in the game.
Still persists after closing the game.

 

[Ralston18]

Try reinstalling the keyboard drivers.

Download from Logitech and install per the installation instructions.

Your current driver may be corrupted.