Hey, so I'm using my dads old amp, a yamaha rx v-550. I've connected it to a subwoofer and speakers but when i connect the 3.5 jack into the CS or SS out from the motherboard of my computer, i cant see those options in the audio settings. Its a 3.5 jack into the CS out into the amp, then banana plugs into my speakers. Rca cables for the amp to sub. How do I fix this problem, or is there a special method that i need to follow to set up a sort of 2.1 system on a computer?