Everything should plug into the sub. And then the sub plugs into your laptop. If it does not work when you plug the cables into the sub, then the conclusion would be that the subs circuits are bad. You might try and call on a warranty issue.
Yeah that's the thing, i have unplugged everything and plugged it back in and it still wont work! Also i am not sure if i can get it fixed under warranty because i have lost the receipt and I'm pretty sure the store wont take it back without it.
Any other ideas please! :s