Here are videos of my dash rattle, also getting rattle behind driver's seat somewhere close to side window. More pronounced / unbearable at 4k RPM.
http://www.youtube.com/watch?v=Ax1CJx4iMSU
http://www.youtube.com/watch?v=cX1JjAtXzV4
http://www.youtube.com/watch?v=Ax1CJx4iMSU
http://www.youtube.com/watch?v=cX1JjAtXzV4