I believe the Android versions require M4A audio files instead of the OGG ones computers use.
Thanks for that, but I'll expand. I spent an hour this afternoon converting my OGG files (my compositions...) into the M4a format, especially for Android use. These, original, OGG files were not part of the Android deployment, but, being missing, were source of error when running the Android deployment through my PC's Chrome browser.
My question, really, should be: will this same error arise if run through a 'real' Android browser..? I have no Android devices, so cannot test this.
The answer will be simple enough, I suppose. I only have to upload the Android version to my shared Google Drive, and see if anyone out there would care to run it for me..! So be it; my 'Rachdale Cheese Demo will shortly (about an hour of upload time...) have both a Web and an Android version added...