Quadcopter flipped over. Help

Today it was sunny outside. No wind. Temperature is minus 15 degrees. When I turned on the power, the autopilot was loaded every time, but one regulator squeaked. At home everything was fine. I sat in the car with a quadcopter for a bit and came out again, tried everything well. I takeoff in the stabilization mode and everything is fine in the loiter. After 3 minutes, somewhere I decided to do autotune!
The quadcopter once deviated and returned. And the next time I flipped over already. I suspect that most likely one engine turned off, as it was originally when I turned on the power. In vain I flew. Attached to the topic logs. You can look to help. Can you notice what the problem is. Thank you in advance.

2019-01-09 16-13-10.tlog (859.9 KB)

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