Yeah SSF is on, there's no boost to it and gain is set conservatively. And it's not bottoming out as far as I can tell, it's not bottoming out, I've seen Zv.4's bottom out and they make a sort of clapping sound, this has that messed up coil sound. And yeah alpine, I don't have a clue what's going on, I've only heard good things about these subs and their power handling, being able to free air 2.5k+, and here I am sitting with one that didn't do it in the factory box with less power than they free air.