Squeezebox, including the latest iteration, has always sounded pretty good on my Mac-based system. Lately, I've been experimenting with toslink out of my mac at 24/96 (into a tact 2.2x) as well as 32/178 via a hiFace (64/178 using Pure Vinyl). Not really hearing a lot of difference among the three, but my 57 y/o ears don't hear much above 12k these days.