The problem that we face, is a drift with around 1 m/s to the right when flying in the stabilized or the position hold mode.
We saw in the logfiles, that right after arming the drone the controller sets the setpoint for the roll angle to 10 deg. Whenever we release the manual roll/pitch controll stick into it's neutral position, this setpoint returns to 10 deg.
That's what I think could be the problem for the massive drift. But we couldn't solve this problem with a recalibration of the sensors.