Null states field on AnimatorStateMachine results in internal error

[riasndaz]

Randomly my fx layer is starting to give me a breaking error, i havent imported anything or changed anything does anyone know how to fix this? This problem happens with every avatar except for one and i dont understand why. Every model gets this error except 1337v8 for some reason, and when i take off the fx layer of any of the avis it stop having problems which also doesnt make sense because every avatars fx layer is copy and pasted, then renamed and editted (for seperate toggles obviously).