I use a Musical Fidelity V-Link 192 into my Wyred4Sound DAC 1. It sounds wonderful. I read an earlier post that the Wyred dac upsamples everything. Not so! My Wyred dac displays the proper sampling rate. If it was recorded at 44.1, that is what displayed. If it was recorded at 48, 96, 176.6 or 192, that is what is displayed on both the V Link 192 and dac.
Regardless, the V Link 192 is an inexpensive way to go for a usb/spdif converter. The person I bought the V Link from (bought it used) replaced it with the Berkley USB/SPDIF converter and said the difference in sound quality is very minute and the Berkley sells for at least 4 times the price of the V link 192.