Requested in: https://ticket.wikimedia.org/otrs/index.pl?Action=AgentTicketZoom&TicketID=8561236
If you save a page, audio files in this page, aren't saved. That should be possible, too.
I'm not sure, if this is really something we should do. Audio files can, potentially, be big, which would take a lot of space on the users device. The bigger problem is, that a user mostly can't know, how much space is needed to save all audio files of an article.