I've just purchased a Samsung Galaxy Tab S2 and i've downloaded Spotify and tagged a couple of playlists for "Download". The status remains "Waiting for Download" forever. A particular song will download if I listen to it specifically but not the whole Album or Playlist. I've tried:
1) Deleting App Data & Uninstalling/reinstalling
2) Resetting Tablet to factory and reinstalling Spotify.
3) Logged into my Spotify Account through the web portal and removed all Offline devices and followed the 2 steps above again.
I also have the same issue on my Samsung Galaxy S7 Edge device.