My Throttle has a Mind of its Own!!

[mungee]

I have a Logitech Extreme 3D pro joystick which worked fine with IL-2 1946, but seems to be having some difficulties with CoD.
I have only recently ventured into using CEM and am finding that the aircraft's (Spitfire MkII) throttle appears to have a mind of its own - it appears to move (and rev up) of its own accord (without me having moved the "wheel" on the joystick) and doesn't like going down to 0% - I must add that I have calibrated the joystick using Windows 7 (64-bit).

Any suggestions as to why this throttle is behaving like this?