I'm absolutely thrilled. I have less than a month since the new MacBook (13 "Unibody) and my old PC only for playing music used on my hi-fi system, because the Macbook does not have digital outputs - I thought. This adapter is from the 2-channel jack output of MacBooks (autumn 2009), an optical digital output, thus not only loss-free transmission of stereo content is possible, but also the viewing DVDs with the latest standards such as Dolby Digital or DTS. And although such an outcome is not specified on Apple's website !! My tip: In System Profiler see if a "combo SP / DIF" output is displayed, then provides the jack output with plugging this adapter automatically.
For 1.67 probably one of the best and at the same time best purchases!