After update the firmware to 3.4 rc-1, the GPS v2 is recognized by Pixhawk and I complete the calibration. However, when I put my machine outdoor, Mission Planner always prompt the compass need to re-calibrate. I try to re-calibrate (clear all white spots in the calibration screen and the offset for three compasses is in green color) several times but the problem still occurs.
My machine contains 3 compasses, one is internal, the second one is externally mount. The GPS v2 is mounted in a arm of the machine over 7cm above the arm. The cable is 50cm long.
I need to disable the compass in GPS v2 in Mission Planner to pass the pre-flight checking.