Weird activity please help diagnose

[Joshua Andrews]

Okay so let me start by saying I bout the sub brand new about 4-5 months ago (Alpine type r 12d2) broke it in and had it mounted with magnet inside box q power hd 112 ( cubic air space is 1.50 tuned at 37 Hertz) and I have a quantum audio qs1500d 1500watt amp inside my scion TC /w brand new battery and alternator the day I put system in, I have 4gauge wire for POS and ground and 12 gauge for sub, well after the brake in some songs sounded awesome some not, I turned it with multi meter had my subsonic at about 35-40 lpf at about 100 and the higher bass notes made almost sounded forced and sometimes like it was blown sounding but every other note was amazing also I got on my headunit the bass is at -10 subwoofer set to +9 though anyways so I started messing with stuff and looked at Alpine user manual and it said it gains volume if you reverse mount it (magnet outside box) I did that and a world of clarity came everything sounded better but sometimes low notes sounded clear yet with a added sound it was odd and I would often smell the break in smell after playing some songs (that happened with both normal and reverse mount) well today I decided to turn the gain a bit down since head lights were dimming as well as turned the sub sonic up to about 40 and the lpf to about 70-80 and it was absolutely amazing sounded like a million dollars never had I had that great of power, clarity, and no smell well I stop at a light and right as the bass is about to hit it does for a millisecond then bam silence and I was like WTF seriously I just made the amp work easier and now it gives out well, it came back and sounded really distorted then cut off again and I have a toggle switch as a reminder and I thought ehh I'll turn it off bout 3 minutes later try again nothing then a hour later ( was on a road trip) still nothing so I stopped to get gas and before I shut car off I inspected the amp with REM on at this point the light showed it was working properly the protect mode was not on and I was like ehh **** it so I go inside pump gas and with the car turned off I tried it and bam it worked perfectly with clear sound started car and still works great, and all wires are not able to move neither is amp or speaker but I was just wondering could it be amp about to go out or maybe a short in my car itself, please give me advice/suggestions I tried to cover as much as possible so there isn't any grey area

[Chris from Washington]

Hi There,
Welcome to the forum, this one is a little hard to diagnose.

Without looking up the specs of the sub and amp, I'm assuming you're not running it at a lower impedance then the amp can handle right?
Ex. Running it at 2ohm when the amp can only go down to 4ohm bridged.

I don't think I've ever smelled a sub 'break-in' before, that seems odd to me. I know there is a break in period, but you shouldn't be smelling anything electrical.
How hot is your amp to the touch when things start acting up?