Couple of weeks ago with my P3A I had whilst airborne at about 50 m high a compass error flash up for about 5 seconds. Flown several times since no problem Today at about 80 high same thing happened, this time for about 2 minutes. Then it cleared and all was normal, did a flight afterwards no issues. Both time it went into atti mode Both time 15 or more satellites Different locations Middle of country side. No rf transmitters for miles. Only couple of houses for several miles. I did do calibration today after warning, I dont do it every flight. Any thoughts on this warning ?