Game slows down when client starts moving - Godot Multiplayer

Godot Version

godot-4

Question

My multiplayer game works completely fine ONLY if the host is the only one moving. When one of the clients start moving the game slows down drastically for both players. If you look at the top right hand side of the game in the window you can see a timer and when the client starts moving the timer slows down. This happens to all nodes (that are constantly moving / being updated) in the scene. Why might this be.