I have the rattle in the dash that starts around 40 MPH. Nothing at idle. Could it be this insulation issue? It just started in the last couple of weeks. May have been after hitting pot hole during road construction. The link mentioned here talks about under arm rest. My rattle is more forward and seems to be coming from the middle of the dash. It doesn't come from hitting anything on the road at this point. Its rattling on perfectly smooth roads, but not noticeable until I am going faster.