A couple of weeks ago I crashed my phantom; 2 props broken and an ESC bad. I replaced the props, prop guards and ESC, and it seemed to fly just fine for a few minutes, then it started wobbling and climbing. When it's cold and I start it, it flies fine again for a few minutes and then starts wobbling and wanting to climb. If I leave it in a 5 foot hover and wait, it is stable for a few minutes, then it starts wobbling and climbs to about 30 feet, then descends back to 5 feet. GPS keeps it right on spot. Other than the wobble and the noise it makes when it starts to wobble, the aircraft flies just fine. I've tried in both GPS and ATII modes and I've calibrated the gyros and compass several times. I replaced a motor that I thought was making the noise, but still the same thing. Any ideas?