I'm assuming the app is opening a configured CTI port.
Note, the wave driver provides a way for apps to play/record audio via the standard windows MMIO wave APIs, but it is up to the application to implement code that does something with these APIs.
There is a sample 'answering machine' application available here, which demonstrates some simple media playback from a file via the wave driver:
../../../c/document_library/get_file?folderId=45959&name=DLFE-6078.zip