I have mine mounted on top of my radio inside the fairing and get really good reception.

 

Ditto! I have my magnetic XM antenna mounted on top of the radio chassis, on the inside of the fairing. The navigation antenna is mouted right beside it. My hidden fm antenna is double-stick mounted to the outer fairing. All have excellent reception. I have yet to loose reception. Seems odd that you are having trouble, especially with your's out in the open.