Hi everyone. I'm new here but not to cars or systems at all. I am having problems with my car electrical/ amp / sub

I'm burning up sub woofers after playing for a while the cone gets hot and I can smell the voice coils burning. Everything was professional installed and they can't figure out the problem nor can any other place around here. My amp and sub are matched perfect
Alpine mrp m500 amp
500 rms@ 2 ohms Max
Alpine sws-dw4 duel voice coil 500 rms @ 2 ohms Max 1500 Watt Max power wired down to 2 ohms

All my gain controls were set professional. And were even adjusted to min and Max and still burning up the sub
my 3 sub already

My amp is 3 weeks old and I go through about a subwoofer a week
Bestbuy keeps replacing for free

Also when my bass hits all my lights dim badly and it makes my rpm drop really low at idle

I've done an upgraded battery, the big 3 upgrade
My headunit is pioneer 50Wx4 channels
Front speakers are 6.5 pioneers
Rear speakers are 6x9 pioneers
Also just replaced the alternator last year

My car is a 95 Honda Accord ex 2.2vtec

I have spent so much money taking my car places and no one will give me a straight anwser. I just want to quote burning up subs

Any help and all suggestions are appriated. You guys are my last resourt

 

What size alt (amps).
Where our bass eq set at?
Where your gain set at?
Whats your voltage at the amp when playing and car idling?
What sizs of wire for power and ground?
Amp conected using rca's or hi level input?
How high you turn your volume on hu up to?
What is the exact model of the hu?

If possible have them replace both the amp and sub.

 

What type of enclosure is your woofer in? is it a generic box? (Bassworx) , custom box ?
You had mentioned as well that you did the big 3 upgrade, where is the ground cable grounded to and how long is it? As stated above by Sonic what guage of wire is used? What type of battery did you upgrade to?