I got in touch with the AV123 guys last night (they sure are a friendly bunch). They had me take out the driver and amp, inspect the inside then re-install everything. Before taking it out, I noticed the amp was a little loose. Also, the four bolts on the front plate were not snug down very tight, likely culprit of the loud leakage. After I re-installation I ran some tests pushing the sub hard. Only at radical levels did I perceive any extraneous noise; so it's now at about 95% of the healthy MFW-15. I'm pretty sure there's still a tiny leak around the driver only heard when pushing it hard. Kyle, at AV123, agreed and recommended I replace the driver gasket foam. So, with that in mind I ordered some gasket-foam tape from Partsexpress.com, expected to arrive on Friday. I'll reseal both the driver and amp and report back expecting 100% performance. Anyway, I'd rather try the reseal than re-boxing the beast and sending it back for a replacement. Of course that's what'll probably happen if my reseal job fails; I'm confident it won't.