I just installed a new head unit, sub and amp. I made sure everything is 100% wired correctly and the amp isnt able to overload the speaker from what i know because the amp is way less powerful and the max rms is lower than the sub. I built my own box based on the specifications that my pioneer sub provided. It sounds great and works really well, but once i push it past about half volume it starts to smell bad, if i turn it down a couple notches it goes away. I am a mechanic and i know wiring well but as for audio systems i only know the bare minimum. Anything someone knows to backup why they smell iffy? Ive heard new subs can have a breakin smell for the first week or so.