The Empirical Audio Freeway 2 takes usb out of the computer and brings it to the Dac of your choice. There are other ( cheaper) alternatives, but you are making some great choices with Kimber, FLAC, etc. , so I think you are really close to great sound. Have fun.
Best Digital Input from PC to DAC
I'm currently using a Kimber USB cable from my PC to my DAC to play FLAC files ripped from my cd collection to a hard drive. Although the results are quite good I'm interested in other Goners experience with USB or alternate input choices using a lap top computer for manipulating music streams. I've found that FUBAR and the free ASIO drivers render the best results in play back.