I installed my amplifier & subs in my car on sunday...drove to work, with music blaring, and back...happy as anything...that is until i went to the shops, went over a speed bump and heard a loud bang from the boot....as it turns out, the vibrations from the subs loosened and undone the nuts holding on the spoiler....the bang i heard was the spoiler bouncing on the boot... lucky it didnt do any damage.