I had my installer put in the Infinity 10" Free-Air Sub ( Model Perfect 10.1 VQ) at the stock sub location. The entire area was Dynamated and When turning the volume too loud, it seems rattle or the rear magnet of the sub hits something. It sounds terrible. I am very disappointed and he suggested me to replace free-air sub with smaller magnet. Anyone had the same problem and how do you solve it and what sub do you use ?? Thank you!!

 

I doubt it's the magnet rattling. Try playing a song that's known to cause a rattle and hold your hand over the panels around the sub: the bose panel and the one around it, and the panel that covers the rear speakers. I would bet the panel covering the rear speakers is rattling on the panel around the glovebox/sub area. Mine rattles there. Another culprit could be the panel on the side of the car that goes under the little side window behind the seats.