Can't get sound from all three outputs on sound card

Carp717

Honorable
Mar 7, 2013
8
0
10,510
I just bought these speakers (logitech x 540) used to hook up to my laptop. I bought a sewell 7.1 external usb sound card to hook these up using the three inputs on the logitech subwoofer (front, surround, and bass). I got the sound card working but when I plug the everything in I only get sound from the 2.1 jack output on the sound card. I have changed it to 5.1 Surround on the sound card and even disabled all other sound cards on my machine

The weird thing is when I have just the 2.1 1/8' cable plugged in, I can go to the test portion of the sound card and can click on all six speakers and get sound (even if I have the surround and bass plugs unplugged). However if I only have the center and bass plug plugged in I don't get any sound at all. It seems all of the sound only comes from just the 2.1 output on my external sound card.

I want to use a butt kicker by splitting the bass output into a separate amp so I need to know how to get sound from all 3 outputs when using 5.1 Surround. Any help would be greatly appreciated. Cheers!