title: Adjust the length of an AudioUnit Buffer
body: <p>my Problem concerns AudioUnits. In order to design a voicechanging App for iPhone (with Objective-C xCode) i use RemoteIO audioUnit sample from this website:</p>
  
  <p><a href="http://atastypixel.com/blog/using-remoteio-audio-unit/" rel="nofollow">http://atastypixel.com/blog/using-remoteio-audio-unit/</a></p>
  
  <p>The audioUnit buffers are set to a length of 256 samples. For my project i need alot more (about 22050).
  The quoted page says that the length of the audioUnit buffers can be adjusted like this:</p>
  
  <pre><code>float aBufferLength = 0.005; // In seconds
  AudioSessionSetProperty(kAudioSessionProperty_PreferredHardwareIOBufferDuration, 
                          sizeof(aBufferLength), &amp;aBufferLength);
  </code></pre>
  
  <p>Now my specific question: The code above is not suitable for the mentioned audioUnit, because AudioSession is not used, never initialized and therefore produces an error.
  Is there any other other possibilty to adjust the buffer-duration except for "kAudioSessionProperty_PreferredHardwareIOBufferDuration"?
  The documentation is not quite useful in this case...
  Thanks in advance, Lukas.</p>