SP-2500 subwoofer blown?

Hello,

I've had my SP-2500 speakers for about 6 months now. I was just listening to some music at moderate volume and the sub just went out. I've tried a number of things, including making sure the sub isn't muted, making sure it isn't on late night mode, and trying it with different audio sources. It really seems like my sub is dead now.

Any suggestions of anything else to try? Would my speakers still be covered under warranty (bought new from compusa.com in July 2011) and would I be able to get a replacement sub?

Thanks for the help.

-Will