Stop Avatar Rotation?

I have an object that when an avatar sits on it an animation starts. I linked a rotating multi-prim object (xy axis the same) to it. Now when the avatar sits, it also rotates. I managed to set the texture rotating in the opposite direction to null any visual rotation. Is there a way to stop the avatar from rotating? I've read some stuff on avatar rotation while not sitting but I don't know if it applies to this situation. All help is greatly appreciated!