2 of my speakers from genius SW-5.1 1505 are not working?

I plugged in my new stereo system, a Genius SW-5.1 1505. Everything was working fine, all speakers+subwoofer were working until yesterday. The SL and SR just stopped working. The rest works perfectly fine, except for those two. I have tried everything to make them work but nothing has been working. My sound card is a Creative Sound Blaster X-FI MB and it's managed by IDT HD Sound service. What should I do?