@echolane Firstly, the USB cable will be a type B from your PC to a type A to the DAC. I am not aware of your PC setup, however music player straight from a PC USB port will have jitter error. There are intermediate plug in solutions for that mentioned somewhere in the current topics in A'gon.
Again, I am not sure what program you are using to play your music, but file format and driver can effect the music quality. You might be tempted to source an expensive USB cable up front, but from my experience, don't, at least not yet. Get $20-$50 cable and you will see that the music is not bad. It may be quite acceptable for quite a while as the main issue is the PC. I am not sure why posters immediately quote $300-400 cables first up!
Have a look for products on this forum for re-clockers such as Synchromesh, unless your DAC already has a jitter eliminating clock.