[KevinH]

Not much you can do until the Readium/Thorium project bug fix gets picked up by the various projects that use it as the basis for their reader software.

Your code is correct, it is just a limitation of the current versions of their Reader software. I would guess Books (iBooks) will work in iOS but I am not sure what would work on Android. If Kobo has a reader for Android, have you tried that?

FWIW - just tried Books on iOS and it works just fine with audio and video.

And the BlueFire Reader on iOS works just fine with it as well.

And even the Kobo app on iOS will play it correctly but you must use two fingers at the same time to tap the play button and not turn the page instead.