DAC doesn't recognize hi-res files

your dac recognizes USB only as 24/192. you need today's technology dac and not mac. for mac you need usb-sp/dif converter and use rca input.

You have 2 options.

1. Open up Audio MIDI Setup
It's in Applications/Utilities or you can search for the program using Spotlight.

Click on the device for your USB DAC. It should say C50 or something.

Click on the "Output" tab.

Set the format to 192kHz. It is probably stuck at 44.1kHz at the moment that's why Mac is downsampling your hires file down when sending it out to the DAC. ps Windows 7 also does it this way so it is not specific to Mac. It's just that these operating systems weren't originally designed for music playback.

The problem is that when you set it to say 192, it will output everything at 192. Even your 44.1kHz stuff. Which means a non factor of 2 up sampling. And most OSes do a frankly crappy job of up sampling.

So ideally you should be switching the settings in Audio MIDI to 44.1 when you are playing 44.1 stuff, and 192 for 192 stuff etc.

Not an ideal solution but it can work.

Which leads us to Option 2.

2. Use an Add In program to iTunes

These programs include "BitPerfect" - about 10 bucks, Audirvana Plus, Pure Music and Amarra with increasing levels of cost (going up to 100s of bucks).

These add in programs disable iTunes playback engine but uses iTunes as a way to catalog your music library and select songs/playlists. When they encounter a 96kHz file, they can automatically switch the sample rate accordingly so your DAC receives the data with bit perfect accuracy. Ditto with 192 kHz, 44.1kHz etc.

Most also have superior up sampling algorithms to upsample 44.1 to 176.4kHz or 192kHz (if you really want to).

They also provide memory play - loading the songs into memory before commencing playback. There's also generally an improvement in Sound Quality over regular iTunes.

ps Czarivey is talking out of his ass.

oops I meant 16/44.1
not trying to critique or question at all quality of mac,
but it's still yesterday's digital tech ant not today's
regardless of performance.
Doggie,
try to mask such as arz, snit, cwap etc...-)

Lucid and informative, Doggie, thanks.