I've owned a 2010 HSE for about 2 months. ~55,000 miles on it. I bought it from a friend, but he had it checked by the Houston dealer before I bought it and it received a clean bill of health. Starting a few weeks ago, I periodically started getting a noise that can best be described as sounding like a dry windshield wiper rubbing the windshield, except the wipers aren't on. It happens intermittently---every few minutes--- and usually when I'm traveling more than 50 mph. I get a louder noise followed a few seconds later by several fainter repetitions. It seems to be coming from the front half of the vehicle, but I haven't been able to isolate it. Does anyone have any idea what this could be? Would really appreciate the help.