I recently purchased a 97 Cobra with 103K miles thats mostly stock other thatn the exhaust and now the wheels. At about 35 or 40, it start a humming that only happens while accelerating. When you lift, it goes away. This is driving me crazy....anyone had similar problems? Id really appreciate the help.. I thought maybe the Shaft, but wouldnt that continuallly make noise after lifting the throttle?