But it sounds like its the same DAC, which was hiss free with optical. So it's not the DAC "generating" the hiss. Rather electrical "interference" making it ove

But it sounds like its the same DAC, which was hiss free with optical. So it's not the DAC "generating" the hiss. Rather electrical "interference" making it over to the analog side from the digital side. So it's the DACs fault, but maybe it's fair to say that it's harder to make a good DAC when USB is how the data is being delivered. I'm sure a high end USB DAC doesn't have this issue, but I'm pretty impressed with my cheap offbrand optical DAC that was $11. I'm guessing I would not be so impressed with the $11 USB version.