I have two springjoint balls that are exact copies of each other. When placed under the left index finger, it works great. When placed under the right index finger, it immediately 'flies off' like a super-bouncy ball and never comes back (unless I click Reset Avatar).

The ball is duplicated onto the other finger and given its own rigidbody, with the same settings as the other finger's rigidbody. I am seeing this on Desktop mode, 11/6/20, version 2020.3.3p2 as well as the current open beta.