Pinky button can get a build up of crud around it causing it to stick, also just try slackening the screw next to it a bit.
I have had 2 cases of uncalled for button pushes executing, both times i have traced it to bad wiring in the cable from the joystick to the throttle.
If you move your cougar around a lot over time the wires break down inside the cable, causing all sorts of wierd effects.
Try moving the cable around in game and see if anything occurs.