I'm still in the process of checking out my recently repaired H Pro. I've had several flights without problems after calibrations but yesterday when was preparing to fly the message "Switch to Angle mode and land immediately, compass calibration required", or words to that effect. As a test I restarted the drone and ST16 with the same results. I calibrated and all was fine. Could this be indicative of an intermittent problem of some sort? And is there anything I should check?