Responsive to an incoming telephone call, a session server consults
pre-stored caller preferences to generate a source file of caller-specific
audio content, then conducts an interactive playback session audibly
presenting the content to the caller. Each call's source file may include
an internally stored history record documenting events that occur during
playback, such as caller utterances, identity of audio content presented,
voice prompts presented to the caller, errors, and time stamps of various
playback events. In response to certain caller utterances or completion of
the source file's presentation, the session server may reference the
history record for guidance in creating an appropriate follow-up source
file containing appropriate supplementary audio content. Use may also be
made of history records for purposes such as increasing the functionality
of interactive user playback, providing billing records, aiding debugging,
and preserving data that is useful for marketing purposes.
