I've seen mentioned in several threads that there is an "enclosure" for the subwoofers in the rear package tray for the THX system in the LS. I don't have any kind of enclosures around the speakers in the trunk, they're just exposed to the interior of the trunk. Is that correct, or am I missing the enclosures? The bass, even at low level, sounds very distorted at certain frequencies, but phenomenal at others. Thanks for any info guys! Also looking for the latest map if anyone has a plug on that!