Xbox Controller and Unity Buttons UI

I'm on Mac and finally could install everything to make it work. I can navigate throught buttons but i cannot do the Select part with the A button (16 on mac, 0 on window)

I'm using one Xbox plugin i found and it detects when i press the A button (or any) so inside and update i'm doing this

 if(XCI.GetButtonDown(XboxButton.A, controller))
         {
             Debug.Log ("Button: " + es.currentSelectedGameObject.GetComponent<Button> ());
             es.currentSelectedGameObject.GetComponent<Button> ().Select ();
         }

It debugs me the currentSelected Button but it does not Select it like if i press return or with the mouse click.

Anybody know?