So I just got home from flying yesterday and I had a weird experience. I did a IMU and gimbal calibration today. I went to my location, did the usual compass dance, put it in the air, stable, put it up about 80 feet and started flying and got a compass/atti mode error and I pulled it back real quick, it kept drifting as it said it went into ATTI mode, my heart sank for about 3 seconds because it just kept drifting and GPS finally kicked back in. Rest of the flight was ok. What would cause it to do that?