The CloseAudioOutChannel API procedure is called to close a previously opened audio output channel.

The GetAudioOutSampleBlockSize API procedure is used by application software to determine the sample block size the audio output requires.

Application software calls the GetNumAudioOutBuffers API procedure to determine how many audio output line buffers are available for use.

The OpenAudioOutChannel API procedure is the first API procedure that must be called before attempting to stream user defined audio data to the telephony engine for playback.

Audio outputs can only be opened once. That is, calling this API procedure more than one time per audio output will result in an error.

The SetAudioOutBufferEvent API procedure allows the telephony engine to signal the application software when audio output buffers are available.

The SetAudioOutDataType API procedure allows the user application to specify the format and rate of the data it will send to the telephony engine's audio output.

The StopAudioOutput API procedure should be called by application software to immediately stop the streaming of audio data to the audio output. This includes any audio data that may be queued up internally.

Call the WaitForAudioOutComplete API procedure before closing the audio output channel. Doing so will ensure that all queued audio sample output data gets played. If an audio output channel is closed and there is queued up audio output data waiting to be played, the queued up data will be discarded.

The WriteAudioOutData API procedure should be called by application software to stream user defined digital audio data to an audio output.

Application software can stream audio data to an audio output at any time so as long as the output has been prepared properly using the other audio output API procedures.