Didn't help at all. See this post.Let me know how it works out
Last night I added Kilmat to the metal behind the enclosure and rubber washers between the enclosure and the mounting points. Unfortunately, by the time I was done, it was too late to test at a high volume. Will give it a try on the way home this evening.
If this still doesn't solve the rattle, I will pull the enclosure again and cover the outside of it with Kilmat.