Yeah man, I totally understand you. I have the same problem and its sorta getting on my nerves, too. Its not so much a problem from the inside, but from the outside you can hear it. Go on ebay and search for "scala1" he is
www.ikesound.com and sells like 36 square feet of Dynamat Extreme (best thing youd want) and that does a good job at stopping the rattling, its about $107 dollars (Yikes, it is a lot). If you havent done so already, get something for your License plate if that rattles, thats what I did at first. I just got some rubber things to put under the 4 screws.