I mean, i have made a simple setup: 2 active hardbody spheres with some initial velocity, affected by a gravity field colliding with a pasive hardbody plane.
When i hit play none of the two spheres will have exactly the same trajectory...(at the begining yes but let it run 600 frames and it starts to differ)
I havent noticed that before and Im no adept of dynamics but... is that a normal behavior?

(at the beginning i tought it was that i turned the second sphere into a soft but repeating the setup to before that point the trajectorys remained non-deterministic...)