Matt00, there's no agreement of which program works best, but the most commonly uses ones have all been mentioned; Audirvana+, Pure Music and Amarra for Mac. Jriver for mostly windows, and recently added for Mac.
With one of those instead of iTunes from USB to your dac, you are well on your way, but not yet the best SQ.
The two big themes are power supply noise and USB noise. A million threads, cables, tweaks etc all point to cleaner power and more isolated quieter signal. With USB carrying both signal and power in a little cable and one connector there are many challenges being tackled by all kinds of approaches. Computeraudiophile.com discusses them in more detail than is typical here, but if you invest a little research time you will get up to speed quickly. Cheers,
Spencer
With one of those instead of iTunes from USB to your dac, you are well on your way, but not yet the best SQ.
The two big themes are power supply noise and USB noise. A million threads, cables, tweaks etc all point to cleaner power and more isolated quieter signal. With USB carrying both signal and power in a little cable and one connector there are many challenges being tackled by all kinds of approaches. Computeraudiophile.com discusses them in more detail than is typical here, but if you invest a little research time you will get up to speed quickly. Cheers,
Spencer