Strange sound highway speed with bags

3 years in ownership of this bike and have never heard the sounds that I heard today. Heading north on 95, 75mph and windy! I noticed a sound almost like a heat Shield scraping sound on a car. I pulled off a few miles up and inspected my bike. At first a I thought the center stand was loose? Nope. Looked everything over, all looks normal. The only thing that has a little play are the bags and the little red reflectors on license plate holder. Only makes this sound at speed in a lot of wind on highway. Didn't hear a peep on back bumpy roads.

Any thoughts?

I will check that out, thanks.

Mike