Sell that as fast as you can.....
j/k man.....seriously though, we've had a ton of problems with MTX subs in general at our little shop.....cones cracking mainly. They've got to be the cheapest and thinest woofer cone ive ever came in contact with in the 20 or so years ive been at this. Its just a hair up from paper, but even paper gives SOME and doesnt crack. I can supply you pics of MTX 9500's with cracking issues if you wish.
Id just sell it and trying something else that fits your amp well.