A:Answer There are some videos about fixing subwoofers on YouTube. But there is something else that worth trying although that might not be the case here or you might have already ruled that out by using aux. If you are hooking it up to a windows machine, when you connect it, the OS would ask you about the output type (headphone/small/medium/large speaker.) If you select small speaker or headphone by mistake, the subwoofer stops working properly when playing through Windows. If that's the case, just taking the plug out and putting it back in and selecting large speaker should fix it. I truly hope that would be the case here.