I recently purchased an iFi iLink USB to SPDIF converter and had some difficulty getting it to work with my 2011 Mac Mini music server and iFi's Tech Support bailed my sorry ass out.
I received mine in short order from Echo Audio in Portland, OR. Shout out to Kurt Doslu and the best B&M store in the Pacific Northwest, IMnotsoHO.
Unpacked it, installed it between DAC and preamp and no sound. Hmm...read the manual but no installation instructions, checked the iFi website and nothing there. So I opened a ticket.
Worked with Alix through the entire process of him (her?) teaching me how to setup a device in Mac OS. I knew nothing. Kudos to iFi for keeping the same person on an issue from beginning to end.
It took almost two weeks because of my work schedule along with other distractions that only allowed me to work on it for a few minutes to an hour at a time combined with two blocks of three days where I could not work on it at all. Alix was polite and incredibly patient through the entire process.
In the end there, of course, was nothing wrong with the iLink just my lack of Apple knowledge.
Thanks again to iFi and Alix for triumphant success in spite having to deal with an end user like me.