Unstable Qstabilise


I am building the Fighter Vtol kit from MFE using the CUAV x7 Pro Controller.
Quadplane motors are T-Motor v505 260kv driven by Flame 60a HV ESC.
Setup running on 12S (2 x 6s).
After wiring and calibration i tried to do my first hover in Qstabilise but the plane would not get up ( heavy oscillations in Plane 4.0.9 so i tried 4.1 Beta)
In 4.1 Beta, plane takes off at first but then the oscillations return progressively (as shown in the video)
I also attached the log file.


I am new to planes. I am using the exact same FC for a hexacopter that flies very stable with out of the box pids.

Could someone please point me in the right direction for solving this?

Thank you very much,