Odd behavior on 3.4.1 from Drift mode

I flew my HC 550 hex this morning to test all the flight modes switching from altitude hold to GPS mode etc.
When I tried drift mode the craft responded very well, so I switched back to GPS (quite windy).
When I treid to get the craft close to me I noticed that the yaw and aileron channels had switched !! so I brought the thing down.
Unfortunately I didn’t have the presence of mind to let the pixhawk dissarm of its own accord, instead moving the yaw stick to the left to dissarm as usual.
As a result (of the channel switch), the craft flipped over and now I have a broken roll arm on the gimbal.
Not having experience with logs. I would be grateful if someone could have a look at the one attached, and comment.
I did notice from the video footage that there is considerable vibration from the frame, although the props ahve been balanced…
2017-03-29 11-51-23 43.bin (1.7 MB)