Parenting prop to bone causes bone origin the change

Hi, I have this very strange problem, whenever I parent a prop (simple mesh) to a bone in my model, many of the bones in the model suddenly start rotating around the prop, instead of at their own origins.

example: I parent a ring object to a finger bone through code:

ring.transform.parent = fingerbone.transform

or :

obj.transform.SetParent(fingerbone.transform);

Now, instead of the arm bending at the elbow as usual, including this one c# statement causes the arm to rotate around the ring and the elbow to stretch out like a rubber band

Same happens when I create a simple cube in the editor at runtime and parent it to the hand of my model in the scene hierarchy..

 

Never mind, seems it only looked like the center was changing due to the pivot settings of the editor being set to Center