with Mac's (and some PC's I imagine, you do not NEED a USB DAC or input on your CD player ... the Mac Mini provides digital output thru a mini optical jack. you just need a mini to toslink adapter or better yet a mini to optical cable like the Van Den Hul. Of course you need a DAC with toslink input but this is pretty easy to find. You could also use a USB to SPDIF converter like the Hagerman.
good luck!
jeff
good luck!
jeff