My 2006 Civic EX coupe is having the same problem. The noise is apparent only at speeds above 30 mph. It sounds to my like my tread area on the rear driver side tire has a small bulge in it. I thought it was due to the Bridgestone tires it comes standard with (about 12 years ago I had similar problems with Bridgestone tires and have stayed exclusively with Michelin tires ever since then). What is a tsb? Trouble Report Bulletin?