AIR not yet compatible with Yosemite for MAC

[Antoine]

I'm not sure as to the why myself. It looks like AIR is perfect for non-optimized systems (and give you say 85% regardless of the system used or how it's configured) but can become a bottleneck at a certain point in time when you're making the optimizations. I've only realized/experienced this myself over the last few weeks but was surprised that I wasn't getting the results others (not Devialet users) did and it turned out switching to USB lifted these "restrictions".

A lot is written about why optimizing a PC/Mac helps improve SQ. But no one can really explain this for the full 100%. A lot of it seems to boil down to a need for an optimized power delivery (as clean as possible, with separation of/dedicated power to, for example the power to a SSD or USB interface) and a low latency almost real-time connection to a DAC and a computer that performs the least amount of concurrent tasks and processes. AIR is anything but 'real-time'/low latency so perhaps this is a possible reason. (just a thought)