is there something wrong with my sub

[dtowntke]

i purchased an open box subwoofer from american tv and appliance. when i bought the product the girl that sold it to me told me that another employee had broken off the end of a subwoofer cable in the lfe input but they removed it and it will work fine. but to make a long story short i am running 2 subs the energy e.s12 (open box) and an polk audio psw 303 8 inch sub, i have them at about the same level on there on board volume level and obviously there set the same on my receivers sub volume level and the polk is louder so i was wondering when the guy broke off the cable in the lfe in could he have messed the amp up on the sub or the way my sub cable is connecting to the woofer or dose my sub need to have more juice(i dont think the juice is it because its own amp supplies that right?)? its still under warranty but before i unhook everything and drag myself and the sub out into the cold i was wondering if maybe some one has some insight? let me say that the sub dose play and it will pound at high volumes, i have checked and double checked and everything is hooked up right