Wobbly colliders

Here’s my problem: I have multiple objects with box colliders but when I put more than (lets say 4) on each other, they’re getting Wobbly and it seems like object are getting a little bit inside each other…
Is my computer not fast enought to follow with the colliders (I don’t have a bad one however) .
Or Do I need to change the collisions settings? Continous or Continous Dynamic don’t seem to change anything…

(Hey Sorry I’m french, I Hope everything is clear, THANKS guys <3)
(If it’s not clear, I’ll try to explain with different words, sorry )

I would be super happy if someone could answer <3