I've been using Movie 15 to create narrated PDF files. Works well in Adobe Acrobat and may soon work on the iPad, too (pdf readers there are promising to handle embedded sound). But Movie 15 is now "deprecated".
The replacement, Media9 seems to depend on a Flash engine (built into desktop Adobe Acrobat readers) to play media including sound. Bad choice, it seems to me since, in addition to IOS which is Flash-free, Flash is disappearing from Linux, desktop browsers and possibly elsewhere.
Is the "deprecation" of Movie 15 going to be a problem for its continued use? Is there an alternative way to embed sound in LaTeX-sourced PDFs?