How are you connecting the sound card to your sound system?
When using SPIDIF, high-quality digital signals for all six channels (5.1 max) run directly to your sound system without any enhancements.
I'd suggest to use analog connectors if you wish to utilize all the sound enhancements the card offers. Older 5.1 sound systems will have direct 5.1 inputs, use RCA->RCA for the front channels and two 3.5mm Stereo->RCA cables for center/Subwoofer and rear (you can leave side channels disconnected for 5.1).
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FPS, Racing, and VR Gamer / Tech Enthusiast / ROG Admin