The player calls this function to pass audio data for rendering.

The module should either render, cache, or ignore the data passed. The module does not have to return from this function until all the data is used. In the case where the playback module has been paused, this may be a lengthy wait, as the data may not be able to be processed until playback resumes. 

Provisions must be taken to maintain the marker with the audio data passed in writeData. The module can use the marker to advance the progress of playback and to provide synchronization.