Spotify Android App will not play Local Files (M4A / ALAC)

[snakefoot]

I have created a Playlist and made it "Available offline" on Spotify Destop (Windows 10), and retrieved it on my android tablet (Samsung Tab3 Wifi).

Spotify Desktop will properly recognize M4A / ALAC files and play these fine locally (When 16 bit). And they will also synchronize to the android tablet.

But the android tablet doesn't give any sound when playing. The progress bar for the song moves correctly but no sound. I have tried to put a MP3 files into the playlist and it plays with no issues on the android tablet (M4A / AAC also works).

How do I make the android Spotify App play M4A / ALAC files?

-Rolf

P.S. I have tried to clear local storage on the desktop and also reset the android spotify app, and resync, but the problem with M4A / ALAC remains.

P.P.S Example M4A / ALAC file can be found here (Hallelujah lossless.m4a)

http://www.thesixteendigital.com/testfiles/

[snakefoot]

I have submitted the following idea about optimizing local files for mobile devices:

https://community.spotify.com/t5/Idea-Submissions/All-Platforms-Playlists-Optimize-Local-Files-for-M...