I blew my Def. Tech. Pro Sub 100, but luckily, it was still under warranty. The guy I bought it from was pretty shocked. He asked if I was playing rap, like because I'm a teenager, that's what I'm supposed to do. I kinda grinned and told him, "No...Nine Inch Nails, thank you." Anyway, apparently it's rare, but I did it. I was told to press lightly in small areas around the driver and listen for slight scratching noises. If you think yours is blown, try this. If you hear scratching by manually moving the cone, it's probably blown. Hope it's still under warranty. Good luck!