Can't play songs after downloading

[whoisfi]

After I've downloaded songs, I can't play them anymore at offline mode. This only happens if I save data on SD card, but if it's on phone memory I can play song in offline mode. I tried to check why this happens and it gave me this.  [ http://prntscr.com/hzgp47 ]

The [ android/data ] folder which is where the downloaded songs encrypted is supposed to be saved but instead it auto hides all folder, sometimes create a folder named [      .   ] in which I can't rename or delete and it's 0 [zero] bytes in size. Note that this only happens on SD card and not on phone memory. If only I could choose specific folder path maybe that could fix the issue.