Document Revision History

This table describes the changes to Audio Unit Properties Reference.

Date	Notes
2012-12-13	Clarified discussion of voice processing I/O audio unit properties.
2010-12-16	Added descriptions of new APIs for iOS 4.3: `AudioUnitParameterHistoryInfo`, `kAudioUnitParameterFlag_PlotHistory`, and `kAudioUnitProperty_ParameterHistoryInfo`.
	Added descriptions of additional Voice-Processing I/O unit APIs: `VoiceIOFarEndVersionInfo`, `kAUVoiceIOProperty_FarEndVersionInfo`, `kVoiceIOFarEndAUVersion_RequiresBackwardCompatibility`, and `kVoiceIOFarEndAUVersion_ThirdParty`.
2010-08-03	Improved descriptions for the `kAudioUnitProperty_MaximumFramesPerSlice` and `kAudioUnitProperty_StreamFormat` properties.
	Additional minor improvements.
2010-07-09	Added descriptions for the `kAUVoiceIOProperty_VoiceProcessingQuality` and `kAUVoiceIOProperty_MuteOutput` properties.
	Clarified the description of the `kAudioOutputUnitProperty_EnableIO` property.
	Added descriptions for the constants in “Mixer Audio Unit Properties.”
	Added descriptions for the constants in “Offline Audio Unit Properties.”
	Added information on memory management to several properties: kAudioUnitProperty_ClassInfo, kAudioUnitProperty_ElementName, kAudioUnitProperty_PresentPreset, kAudioUnitProperty_ParameterValueStrings, kAudioUnitProperty_FactoryPresets, kAudioUnitProperty_PreflightName.
2009-06-26	Updated for iOS 3.0.
	Improved description of `AudioUnitParameterNameInfo`. Added descriptions for constants in “Voice-Processing I/O Audio Unit Properties” enumeration.
2008-09-09	Updated for iOS 2.1. Improved formatting for declarations.
2008-07-08	New document that describes the audio unit properties in iOS and OS X.

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