Any chance the brass inserts on the inner fairing are loose or a thread is stripped? Are you using a stock or after market shield? Have you removed the shield to check for damage?
One final thought - unless you have the shield properly lined up it's possible that the shield is actually not located properly over the inner fairing ridge that is around the brass insert (I think this may be what's going on in your case). Take all bolts out, move the shield in place so you feel it click in pace (around "threaded bosses"). It should stay put without the bolts. Tighten bolts to spec (25 in lbs)