This event is called when a double buffer switch occurs within the drivers thread by the CoreAudio drivers BufferSwitch or BufferSwitchTimeInfo events. The following usage scenarios apply: 

• Playback only. For playback use this event to process data stored in OutputBuffers so that user controls can affect the output in real time. (Changing of volume, pitch, playback speed etc...) For data to be fetched in to OutputBuffers, the components Inputs property has to be assigned fetching data from the source (file or other). The stream assigned to the Inputs property and used to feed the OutputBuffers is buffered automatically up to ExtendedBufferTime.
• Recording only. When only recording, this event will also trigger, but can be ignored. Do not use this event to save data to disk or send it over the network. Use OnInputBufferReady event for this purpose.
• Concurrent recording and playback are not natively supported by windows OS.

The event must finish its processing before the next buffer will be required by the driver. Because the event is triggered within the drivers thread, do not use it to write data to disk or to send the stream over network. If the thread will remain blocked for too long time, the recording or playback will be interupted.

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