This appears to be a Google issue, but I'll ask here before creating a Google bug report.
I have a ZTE Zmax phone.
I have 2 MP players (1) ZTE Music & (2) Google Play Music.
Created 9 playlists having (.M3U) extension.
Move MP3 /.M3U folders to music folder on SD card.
After (X) no-of-days of rebooting, the playlists and all songs on Google Play Music disappears.
However, the ZTE 's Music MP player remains intact will all 9 playlist.
To retrieve the missing playlists, I go to setting+apps+Google Play Music and clear Cache & Data.
Return to Google Play Music icon, select playlist and all my 9 playlist + songs returns.
When I turn off phone, then back on or reboot, the Playlist disappears again. Need to do same steps above to retrieve playlists + songs.
Why is this happening?
Is there a permanent solution to keep my playlists in Google Play Music when I boot ZTE phone?
Tried moving music/M3U playlist to Media folder on SD still same issue.
My Google Playlist settings has my Gmail account assigned.
In Google settings, I have sync turned off .
This problem happens regardless if internet is set on/off.
Battery never goes below 50% before I recharge.
I am not signed into Google Chrome on my laptop & phone. Did sign-in same issue.
I did rip the MP3 songs from Youtube. Will GPM reject any MP3 not from it's library subscription?