So my JMJ has a pretty noticeable shielding issue. Especially in my office which has a lot of noises sources - computer, screen, lamps. ceiling fan, etc. Goes away when I touch the strings. So I have opened it up and am in the process of shielding. First I was a little surprised to see no attempts at shielding whatsoever. Not even some foil on the back of the pickguard. But I also see there is no wire running from under the tailpiece to a ground in the control cavity. In the past this has usually been the case. My question is, should I add a wire? Or will it be fine without it...just shielding the control & pickup cavities and applying foil to the back of the guard. Thanks in advance.