I have my box behind the seats (of course) I'm getting this annoying rattle from the box on one side, but when I pick the box up theres nothing. The box is sitting on a rubber stop so I dont think its the truck. Maybe a box issue inside???

 

Is the rattle coming when playing music? just driving down the road? I would maybe try securing the wires to the speakers or any wires that are loose. Maybe tap one screw in to the box to the cab to secure it to the truck and see if that stops it.

 

Playing music. Maybe I have a wire touching the back of sub. Guess I'm taking the box out AGAIN. Thx

 

NP, I was just brain storming on what it could be. Also make sure your speaker is screwed on good and not loose.