1. Open attached project
2. Open scene "Level25"
3. Press play
4. Click on one of connected green balls
5. On collision with white block, ball will fly out of the scene

OR

1. Create new project
2. Create 2 spheres with constraints on X,Y rotation and Z position
3. Connect them with hinge joint
4. Put cube between them
5. Press play

Note: it is easier to repro if upper sphere will have bouncing physic material.