No sound?

Okay, my friend sent me a question and I decided the guys on here would know way more than I do, so here goes.

"I am getting no sound out of my amp to my sub. I am running a rockford t10001bd amp, with a T1 12" d4 sub. I checked my ground, its good, the amp powers on. I think it might be that a couple of nights ago, I blew a door speaker, and it would randomly cut on and off(the actual sound). Could there be a short from this? Also when I was checking the rca cords, I unplugged them, and my amp fuse blew, what is up with that? Anyways, I just really need some help, so any help is appreciated."

if the speaker or speakerwire is shorting out, it would cause the amp to go into protection or possibly even damage the amp.