iainmet: Heres a daft one for you.
Have you got an F Lock key on your keyboard (usually situated above the block of keys above cursors) If you have then you may have pressed it at somepoint and disabled the function keys. Happened to me, use F11 to take screen shots on Steam and it stopped working, turned out I had tapped F Lock and none of my F keys were working!
Thanks but my other F keys work fine in game. I think it's something to do with my Logitech Keyboard as when I hit F11 it also activates an on on-keyboard light indicating that insert is active. I grabbed Setpoint off of Logitech's website and found it did exactly nothing.
I think it's come down to
1. find a way to remap the camera to another key via a config file, or a menu item I've missed.
2. use a different keyboard or
3. don't worry about the camera and just enjoy the game.