Thanks to this book I was able to write my small app (MuteMyMic). As my application is based on low level APIs for sound input/output in OS X, I had to find some sort of comprehensive guid related to the topic. And this is the book I have found the best on the market, so far. Of course you can find a loot of material, that is covered here covered here, somewhere in the web. But when it comes to a single source of the information related to the topic, this one is the best one. Highly recommended.