I went through the trouble shooting and it feels grindy when I push the sub in and out from the center of the cone. I have been told these are bad voice coils. I did purchase this on Amazon so won't hear back from them if I can get a replacement until Monday. Otherwise, how much would it be to re cone and replace the voice coils? And who sells replacements? Can't find anything on JL's site. I called them and left a message as well.