Why is the position of this object not syncing across the network?

in a host only situation there is no wonky physics so i dont know why a client joining also makes the physics go all crazy.

https://youtu.be/zLbOdKuE5M4

here is a video of the issue, i can provide scripts if required however i don't see why my scripts would cause this as currently i am not manipulating anything besides the rigidbodys restraints.