2 weeks into a premium with moon roof. love the new car and have had no complaints until today. at about 70 mph i got a loud low humming sound. hard to explain, but loud enough to be heard over radio. sounded like a tuning fork, low frequency. seems to be on rough part of freeway. dosent happen every time car gets to 70, plenty of times at 70+ so far. maybe wind hitting something a certain way. will keep monitoring.