Mixture control in Spitfire

[hugso]

Since the new patch via Steam and the Spitfire now being ready for takeoff with the engine running and warmed up, my mixture control slider does not operate in game. I have tried resetting it in Controls, and it seems to be recognised, but no movement in game. Is it me, or is this correct? Also, does anyone else find that switches, such as for gear up/down, sometimes need operating several times before being recognised?