Constant gaining altitude at idle position of Logitech extreme 3d pro problem...

[cronustr]

I have calibrated my Logitech 3d pro, at Windows. I have no problem with il2 1946 but at COD, when I release the joystick at idle position whatever the model is the plane nose rises and gains altitude.

I've set the sensitivity and lowered, aiming is now easier but to fly straight without gaining altitute, I have to move forward the stick and keep it there for all the flight.

What is the setting or settings that I can fly my plane straight? Am I doing something wrong?