Weird actions form my subs

[Florida240sx]

I'm almost sure they are blown. Don't sound like they are at the same db level as before. Same song same volume same settings. Had the ground on my cd player go bad and speakers were distorting like hell. When I turn my key off my subs hit hard but more of a distortion hit. Sounds like the are popping. So if my speakers are blown would they do this or am I still having a ground problem? or something else?

[Rex]

I'd say if you're having a "thump" at turn off, you still have some sort of electrical problem. I'd pull the fuse and disconnect the subs until you can figure it out. This type of "uncontrolled/distorted" abuse is what kills subs/speakers.