I am clueless about what I am doing wrong. I tried to calibrate gyro and accelerometer in all six positions while keeping it still as much as I can, I cannot imagine that it can be more stable during calibration (fixed firm to bubble balance without holding by hands).

When I turn the controller on, it stabilizes the camera, but its neutral position is not leveled and it is drifting slowly along all three axis:

https://youtu.be/lvs-X2MWyGo

I use GUI 2.43 b9 and the same firmware. All three meters in GUI show correct orientations when moving the sensor.

Never had such problem in my previous two gimbals of other types, even out of the box, with no calibration at all.

I would very much appreciate any suggestions.