kicker comp vr 12, alpine mrp-m500

I have a kicker comp vr 12" dual voice coil 4ohm wired parallel to make it 2ohm and a alpine mrp-m500. in a sealed box in a extended cab s10, and when i turn it up it doesnt sound good and if i turn it up more it cracks and pops really loud. i tried another sub(the same kind). also had a smaller amp so i just bought this amp. and it sounds the same. thanks in advance

Popping sound is constant, and increases with volume? Can you hear it without music playing between songs?This is what I do for FUN!

no its not consistent. it is when i turn it up. it doesnt sound right at all. but the popping is only when i turn it up. im running 4gauge wire and using the same ground point as my amp for my other speakers. but im not sure what would cause this.

i tried with another kicker comp. and it still acts the same.

commercial-....and ACTION! Dont risk the $200 investment with your 12" subs and 3000 watt amp with any enclosure. Only RoXBoX knocks the others off the blocks, custom rocks in the box, that rocks- RoxBox!!! Now featuring the RoXBoX-4500x Converted Marble series! commercial-....and CUT!...thats a rap! I've heard that sound from poor enclosures or faulty input signal received by the amp. I'll have to assume everything has been checked for any faulty physical technicalities. Other tech's may have a direction to lead to, but the simplest troubleshooting method as you may know, is to always refer to a known good. First, using a meter-know that the electrical properties are reading as they should. Checking a known good signal helps a lot. I use a media player with a phono/stereo RCA adapter to bypass the source and plug right into the amp. Is this amps input signal a sub/out from the deck? Carefully try to swap RCA's in the dash and see if the front channels, on the sub line, do the same thing.This is what I do for FUN!