title: AudioUnitInitialize failed with error code 1852008051
body: <p>I'm trying to record with Audio Unit in iOS.<br />
  I set componentSubType in AudioComponentDescription to <b>kAudioUnitSubType_VoiceProcessingIO</b>.<br />
  Then both of AudioUnitInitialize and AudioOutputUnitStart's error code is <b>1852008051('ncfs')</b>.<br />
  I cannot find this error code in the document.<br />
  But when I turn <b>kAudioUnitSubType_VoiceProcessingIO</b> to <b> kAudioUnitSubType_RemoteIO</b>, everything is just fine.<br />
  Could anyone tell me what should be modified when changing from VoiceProcessingIO to RemoteIO?</p>