Blender Animation ?

Hi, i'm trying to share animation between models. I know that there are other questions about this but my problem is another. The armature is the same for all characters and when i share the animations, all goes to the right way. The problem is that when these animations are played, other part of the model ( not the mesh with the armature), move,rotate and scale casually: but i don't have set anything of this parts (Loc or Rot or Scale) in these animations. Example : a human move to the right way his body, but the hat is rotated or scaled. All these parts are different object, so aren't in one single mesh , but are in the same model. Using ctrl+A for set pos,rot and scale don't help. Thanks in advance and sorry for my English.

Thanks for the help. This is an invented character so the arm with his armature is a single mesh. Then there is the body that is also a single mesh and then the clothes (single mesh) and the hat(single mesh). Are all subdivided because in this way i can animate some mesh with rot,loc and scale without using shape keys. Also if i add the armature to the arm in a different file and then import it to the character, when i play the animation (made in the different file and so, no weight painting on clothes or hat) , clothes and hat are scaled or rotated.However, thanks.