My '10 ES350, with 124,000 very smooth miles on it, has developed a sound that "resembles" a cupping sound from feathered-edge tires. My tires were about 2/3rd's gone, so I purchased a new set of Michelins this weekend. Had a 4-wheel alignment done, it was near perfect - no adjustments made. Sound is still there. First, while driving on asphalt, on a straight stretch, between 30-40 MPH, it is very evident. Then, while driving through "s-curves" on smooth asphalt at 50 MPH, it is even louder. I am at a loss for diagnosis. Any experience with this from you all? Any input is appreciated.