I have an app called minilyrics, it has a function to download lyrics on mp3 folder and though the option is selected mp3 are stored in other path. I have used same app in previous android4 devices with external SD without problems.
From the same app, the browser folder function displays some paths, just the following:
/storage/0000-0000 (external) and all folders containg mp3s /sdcard/Samsung/Music (1song) /sdcard/Whatsapp (1 song)
Curiously, Minilyrics can play mp3 from the external mem (SD) but the app doesn't download the .lrc files on the mp3 folder but on:
/sdcard/Download Alias of /storage/emulated/0/Download
I dunno if this problem affect to all android 6, note4 or any Samsung note devices.
How to check where is the source of the problem? Any tip about path mapping and eternal SD cards?