EDIT: Problem was Motor1 and Motor2 were exchanged. They were turning in the correct direction and allowed a stable take-off and hover on this Y6. But any control error would build up and let it loose yaw authority.
I am facing an issue with my Y6B. Intial tests and tuning flights were successful. Only best compass used, in-flight calibrated.
When doing first max throttle test I had a deync+minor crash.
Fixed a prop and set Blheli less aggressive.
Then on the next test flight the copter took off fine, for the first two 2 seconds no yaw error and then it suddenly just starts yawing.
First thought was of cause that its someting mechanically, checked all props tight and plain, turning directions right.
Also did a calibration of all 3 compasses and used them.
But on the next flight-attempts the problem presists.
Its a bigger copter and with this problem it is a bit dangerous to start it. I would appreciate if somebody could have a look at the logs for anything suspicious.