Physics Interpolation Weirdness

So, one of the things I'd like to do in our game is have slowdown stages (and speedup stages). We basically just lower the time scale and pitch all of the audio. It breaks up the pace nicely.

My understanding is that the Rigidbody interpolation setting is supposed to be used whenever you have many more graphical draws than physics updates.

So I did a test with 0.1 time scale (0.01 fixed timestep), and set interpolation on everything physical.

It works fine on the pies. They're smooth as silk. The ragdolls flap like birds, though. Do the constraints of the ragdoll not play well with interpolation?

Video: http://www.flashbangstudios.com/tests/ihc_interpolation.mov

Extrapolate also looks wrong, but in a slightly different way.

By the way, the crazy audio warbling seems to be a symptom of the timescale alone. If I remove the pitch code and keep the timescale to 0.1 the sound is still very odd.

 

Oh, I forgot to mention it starts throwing these errors too:

 

I'm not sure I understand your issues, but I've had similar "flapping" problems for some of my physics joints when two colliders were either too close or overlapped.