If your sub is still on warranty, please have it replaced by Klipsch at the earliest. They should replace it with the newer model SPL 120. Its a well known issue looks like with R-112SW eventually failing with these kind of symptoms. Apparently the issue has been linked to poor electronics inside(black goo of death). I had raised a query with Klipsch earlier since I have two of these, and they said they have fixed the issues. Not sure how far that's true as I continue to see people complaining about these rampant failures with R-112SW. I am living in fear to see the eventual death of my dual R-112SW. May the (low frequency) force be with me.