Issue title: Compass spins after calibration in APM 1 , while in ver 2.8.1 works fine
 Issue body: after upgrading to ver 3.0.1 , and doing calibrations , the compass heading is not fix , and spins all the time, put back ver 3.0.1 , works fine
any ideas?

 Comments: 
 Comment 0: BUG

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