Bone trembles while using large gravity

[WXGopher]

We've found that large gravity parameter (z = -5000 for example) will cause bone trembling/shaking.

We wonder if anyone would have any ideas/inputs on this.

Thanks!

Here is the setup:

P.S.
I think this is what was causing the trembling:

Bone.Location += (BaseLocation - Bone.Location) *  (1.0f - FMath::Pow(1.0f - Bone.PhysicsSettings.Stiffness, Exponent));

When the FPS fluctuates, even if we stand still, we still have the simulated bone pulling in/out of bone pose location (which is given by the animation pose).