Intermittent wind sound 2004 pilot

My 2004 pilot has a intermittent sound around 45 mph that sounds like a piece of sheet metal in the wind. Womp-womp, womp-womp. I have had the entire under carriage examined and nothing is loose or dangling. It sounds like it is in the front passenger quarter panel area. When the windows are down you can't hear it only when up around 40-45 mph. Has anyone else had this experience?:runaround::banghead: