I discovered a problem writhe P2V compass system. It is very accurate... So accurate that the earths abnormalities can mess with it. Today I was flying by a mountain with a red color in the rocks. For anyone in the he Phoenix area I was at the base of Camel Back Mountain. From my first power on the system told me to calibrate the compass. It did but it still flew with much play in the hovering. I chose a new spot and re-calibrate. It still had problems so I chose a new spot again. Still problems. After all that I can only conclude that flying near a red colored mountain (red rocks mean iron, iron is ferris) will mess up the auto pilot flight systems of the phantom. Moral of the story? Learn to fly in non-GPS mode. Just curious. Has anyone else has a similar experience?