I installed an old DAC (Pop-Pulse) to my desktop computer. I use the optical from the motherboard (Asus) to the DAC, then to a headphone amplifier (Keces) to some old headphones (Sennheisers).
It works fine, but then it has starts to develop static/white noise in the right side (no audio). If you reset the PC or reinitialize the output, it will work again. Is there a setting that could cause a conflict?