There is something inside the woofer cabinet that is loose (or maybe it is the woofer cone itself) making a noise that can be heard over the bass during extreme bass scenes (Nemo-Darla scene, U571-Depth Charged scene, etc). Total bummer.
There may indeed be something wrong with the subs driver/amp but my guess is that this is the EP600's limiter kicking in (to protect the driver from over excursion) on those intense bass scenes. I had similar issues with the 600 and other subs I have owned. The only answer is to turn it down or add more woofage.
Axiom gets an amazing amount of output from a single 12" driver but I'm afraid that this design is a bit dated considering the increased LFE in movies and what other manufacturers are doing.
