Plane flips over when RTL engaged

I have tried recalibrating a number of times with no avail,
plane fly fine in manual mode but with RTL engaged plane flips over and ailerons jitter putting the plane in an upside down tail wobble.

When mode switched back to manual full control is gained and able to save the bird.

Any advice would be great

Cheers
Jack

Check in FBWA mode at ground that pitch and roll compensation work as expected in the wiki.

Thanks mate, ill test that out and post the resluts

Finally got round to trying this out again
but now I am not even able to connect to a com port
ill open another thread I guess !