HELP with MAC MINI and PS DIgital III DAC

which input are you using...? Don't think the USB port can support hi rez.

Meiwan raises a good point/possibility...Itunes cannot handle FLAC...I use Max to convert from FLAC to AppleLossless, and it's free and easy to use. Once you convert to Alossless, ITUNES will see and process it just like other music in your library....

AMARRA, while great stuff, is only a front end...and works with ITUNES

HOWEVER, you really need to tell us what you mean by "can't play"

Without knowing where you are stuck...it's hard to for us to tell and help you.

Upsampling and processing and outputting a high res signal are two entirely different things....I really don't think you're going to get high res from the USB port...however, as far as I know the optical will support it.

Good Luck.