Built up my phantom 2 | H3-3D | FPV setup a couple of weeks ago and since then, every flight I have experienced weird erratic movement issues with the gimbal. The most predominant movement was one where it would drift to the left in almost a controlled manner and then it would snap quickly back to the center. I upgrade firmware, downgrade firmware, re updated, calibrated controller............ no matter what, the problem continued... I was getting to the point of checking with DJI about a replacement when I thought I should just go over the installation again. As I started investigating I immediately noticed that with the battery in the phantom (not turned on) there was noticeable friction with the yaw movement.. Take the battery out.. Friction went away.. I needed to space the mount to give the motor clearance so I went and grabbed some thin washers and longer screws at the hardware store. Came back and sandwiched the washers in between the phantom body and the gimbal mount. Got it all put back together pushed the battery in, checked the yaw movement and no friction.... FLYING TIME!!! Gone through 2 batteries now with NO erratic movements not even 1 small twitch!!! The thing is working perfectly!! Definitely do all your updates but check your battery y-axis motor clearance first and foremost because this might be the root of your problem it certainly was mine!!!!