SlugButter
CarAudio.com VIP
The Dayton Audio sub I’m running will make that noise when I over drive the sub also. Your pushing it past it’s mechanical limit. It sounds like metal rattling on metal….because it is. You’re probably pushing too much power to it and also sending a clipped signal to it. That’s the death rattle. You should be panicking to rush and turn down the volume any time you hear a sub doing that. I almost broke my leg running for the gain knob when my Dayton made this sound.