subwoofer rattles like hell

Common sense dictates that, if the unit contains 2 identical drivers, and only one rattles, there is a problem with the rattling one. As was mentioned, check the tightness of the screws on both drivers (always a good idea on subs!). You may also wish to carefully open the sub to make sure nothing has come loose that the cone might be hitting. If there is no obvious reason for the problem and you purchased the sub new, it should be repaired (or they may send you a new driver to install yourself) under warranty.
My credentials: I have been an audio manufacturer for over ten years, an electronic technician for over 30 years, and an audiophile even longer. (IMHO, anybody offering advice beyond what components they like or dislike should indicate their technical background).

Alrau1, it is a push pull configuration so i think if the drivers are pushed too hard it might overload just one of them. what you say does make sense though. problem being i bought it used and it seemed to work pretty good until i made all my adjustments and break in time of the other components, so manufacturers warranty is not an option. it, sadly, was a stretch for me to purchase even used (i'm saving for a bigger house) and i fear repairing will be out of the question. i guess i was hoping for a different answer but thanks a ton for everybodies input!

I just look at the owners manual. The sub has BOTH Hi-level inputs AND outputs with the inputs being the BOTTOM row. Verify your connections, just covering all bases.
Otherwise contact the manufacturer. (go to Audiongon's home page and see manufacturer's list link on the right side for contacts and website).
Good Luck.

thanks for your attention, i had done all those things, i am contacting mirage.