title: In CoreAudio, what are the pros/cons of setting kAudioDevicePropertyBufferFrameSize?
body: <p>When recording from a microphone in CoreAudio, what is <code>kAudioDevicePropertyBufferFrameSize</code> for?  The <a href="http://developer.apple.com/mac/library/DOCUMENTATION/MusicAudio/Reference/CACoreAudioReference/AudioHardware/CompositePage.html" rel="nofollow noreferrer">docs</a> say it's <code>"A UInt32 whose value indicates the number of frames in the IO buffers"</code>.  However, this doesn't give any indication of why you would want to set it.</p>
  
  <p>The <code>kAudioDevicePropertyBufferFrameSizeRange</code> property gives you a valid minimum and maximum for the bufferframe size.  Does setting the bufferframe size to the max slow things down?  When would you want to set it to something other than the default?</p>