I emailed tech support at SVS a few days ago, but have yet to hear from them, so I thought I'd shoot this question/problem to any experts out there. While watching Attack of the Clones at fairly low levels the sub stopped playing the LFE, and starting thumping. It was fairly rhythmic (like a heartbeat), and continued to thump even when I stopped the DVD. The noise it makes sounds like a bass drum. Obviously, something is very wrong, but I'd like to know if it's the driver or the amp that is at fault, or what else it might be. I've got the upgraded driver, and it has performed great until a couple of days ago. Any help would be appreciated. Happy New Year!