I'm getting a gimball overload error, but everthing works fine and smooth.

I have calibrated and updated firmware.  

Blown with compressed air.

Not causing any noticeable issues, but I can't get eror to go away.

Suggestions.

I have also calibrated compass and the other thing (IMU).

I am also experiencing the same thing,  Have moved gimbal around, blown with air while moving.  Also appears to be fine, except for a whirring noise from the gimbal motor.  Not much about this issue on the forum, so will contact the D1 DJI store where I purchased the drone from and see what they have to say.