2011 Chevrolet Cruze LT
So this may be a stupid question, but while driving back to TN from GA several days ago, I noticed a rhythmatic sound while driving at highway speeds. Sometimes it would go away and other times it would come back. I got 4 new tires installed before heading down. When I turn corners, I don't notice any new sounds, it's just while I'm driving at 45+mph, and it isn't constant. What could it be? All 4 tires are the same brand, same tread, etc.