Hmmm it would seem that this better level of vibration changes back to the horrible +/- 10 level as soon as the wind picks up
I'm at a bit of a loss what to try next, all the props and motors are as balanced as I can get them, and yet as soon as I take off I get very high vibrations levels being picked up by the IMU.
I've got some rubber M3 mounts which I could try mounting the AQ on, but who knows if that will actually help. I'm starting to wonder whether this frame is inherently bad for vibration, perhaps partly due to the coaxial arrangement and partly due to the very stuff motor arms sending all the vibration through to the main chassis. But then again there are many videos of it flying fine with DJI flight controllers ... perhaps their IMU is isolated more from vibration (inside its case), given that it also gets stuck directly to the chassis ...
On the other hand maybe I've still got gain problems / a feedback loop which is causing the frame to resonate? Reducing the Tilt Rate D certainly made a huge difference, but I still can't remove a resonant 'zinging' in the frame. Interestingly I can spool up the props until the X8 is light on the skids and the vibration is always around +/- 2, but then as soon as I take off (in wind) it shoots up to +/- 10 ... Perhaps the undercarriage legs are resonating?
Any thoughts are very much appreciated.
Cheers, David