Here's an article written by Jim Lesurf, the science columnist on Hifi News and Record Review (Jun 2011 issue) magazine on why using an Halide Design's USB-to-SPDIF bridge into a DACMagic is (way) better than using an USB out from a digital source directly feeding a DAC:
Damn. A 300 USB interface for a 200 DAC
And that too it can't support above 96kHz.
One should try other options like Audiolab MDAC before going this route which would offer more value with features like Class A headphone amp/ pre-amp for little more amount hyeah: