I downloaded the project and I didn't notice any glitchy movement.
If possible, can you record a short clip of the glitchy movement?
I've let the project run and watched the ball, and sometimes it looks like the ball is jittering around a little, but taking a closer look at it, I think the jittering like motion is actually just a blur caused by the monitor's refresh rate and the rapid movement of the ball.
Slowing the ball down to 100
made the jittering much less visible. That said, I only noticed the slight blur when I was tracking the ball carefully, so this might not be the issue, though it might be something to test.
I did have the physics one do a short teleport, so I changed the physics jitter fix
property in the Project Settings to 1.0
, and as far as I can tell that seems to have fixed that issue, though I have no idea what caused the small teleport. I looked at the code, and I didn't see anything that looked like it would cause that behavior.
With both of the occurrences I wrote above, I had to watch pretty carefully to notice them, so it might be I'm missing something.
Hopefully this helps a bit!
(Side note: Welcome to the forums!)