I'm trying to install my sub and it won't stop vibrating. I had it hooked up while testing it, and everything was fine. Now if I turn on the headunit, the sub just rapid fires as hard as it can (it's shaking my whole house, and my mom's trying to sleep... ) I tried tracing the wiring, but alas, nothing sticking out like a sore thumb. I just don't want to keep tearing up the pain-in-the-a$$ trim in the trunk. And I did turn the gain all the way down, but it still hits if I turn it up at all. Is this a ground problem? An audio problem? Help please. Thanks.

No electronic expert, but sounds like a capacitor in the circuit is defective. Are there any on the speakers, usually at the connections?

Is it only on one channel?

Clear all wires and check for continuity and ground fault.

Can you test the line with another unit?

Bset I can offer now .I will get back with more if I can comeup with something