Crash in loiter after takeoff

Hi,
I’m using a s800 wing with pixracer (arduplane 4.2.1), frsky passthough telemetry. fbwa, fbwb, Loiter, stabilized was working well (compass is disabled, voltage sensor is not working correct, wifi-module was not used on pixracer, FC is mounted 90 deg clockwise).
There was only low wind or turbulence.
I got a problem after starting in takeoff mode: takeoff was doing well, but doing the loiter after takeoff motor was constant on 100% and the wing was rolling over 45deg - kind of flipping - and loosing alt. At the first autotakeoff I could manage to prevent a crash. but at the second autotakeoff I was looking a bit too long…

Can someone give me a hint what was happening?
files can be found at: arduplane - Google Drive

Thank you for your help!
Kind regards,
Gernot