Just installed the gimbal on my Phantom 1. Don't have the upgraded board so had to use a PMU. Made sure I had the latest software update. GoPro was mounted on the gimbal. When I power up, the gimbal activates and goes through some rotations on the axis of the two motors and instead of leveling out, over rotates as if it were aiming backward. On occasion the motors will make a subtle grinding noise which will cease when I move the gimbal slightly. Tried calibrating the trim switch but no change. The trim level on the control has some effect on the gimbal, sometimes causing it to adjust in the expected direction (keeping in mind it is in an over rotated position) but sometimes casuing the gimbal to tilt on a different axis. When I tilt the Phantom, the gimbal, while reacting to the tilting, does not compensate in the expected direction. After approximately 20 secs, the gimbal shuts down. Thoughts/suggestions appreciated.