Recently I purchased a 2009 G37x. I see blurry vision in rearview mirror that i believe from vibration, even on smooth roads. It happens from about 78 - 85 mph speed. At below and beyond speeds are doing okay. I went to the dealer's service center, but they said they can't do anything about this. They made me angry when they couldn't solve the problem and asked me to slow down. Has anyone seen this problem at that speed? What might causing this?