How to configure Mouse/keyboard for FPS games?

[Shonumi]

You can try increasing the dead-zone on the C-Stick, but you'll only notice a difference with the sensitivity if you can actually get it working. Have you made sure that the in-game controller setup uses the C-Stick to look around? Most FPS games let you configure the controls from something like a pause screen. Make sure the one you're using in-game uses the C-Stick for aiming.