I consider myself to be an audiophile. I really like good sound and can hear the differences between equipment, sound file formats, etc. I am trying to expand into using hi-res files (24bit/192khz) from my MacBook Pro into a USB/S/DIF DAC. This is apparently more complicated than I thought. I was under the impression that you could just buy a good, USB DAC, connect it to your MBP via USB, and you're off to the races. Apparently, not so. Could someone help me out? I have a late 2011 MacBook Pro. I understand that the USB only outputs up to 24bit/96 kHz and not beyond. Does that mean that no external USB DAC that will theoretically play 24bit/192 files located on my MBP will actually do so? I also understand that the "optical out" on the MBP (more commonly called the headphone jack) WILL output 24 bit/192khz files. So, is it true that if I want to play 24/192 files I must go through the "optical out" on the MBP and into an "optical in" on an appropriate DAC that has that input and will decode 24/192 files? If all of the above is true, it's a little disturbing that so many DAC manufacturers claim to process hi-res files (24/192) via USB and are Mac-friendly. Apparently, this isn't true. I hope I'm wrong and I just don't understand the jargon enough to correctly read the ads and know what they mean. Can anyone confirm what I said above and share your thoughts about these hi-res USB DACs from your own experience? Any help would be greatly appreciated.