[Android] Tracks sync very slowly

[zikabuk]

• Which device(s) are you using? LG G3
• What version is your iOS? Android 4.4.2
• What quality are you syncing? Extreme
• On which device(s) is syncing slow? LG G3
• On which device(s) is syncing fast (or "regular" speed)? Desktop (W7)
• If your tracks are syncing slowly, what's your average sync speed?
• How many tracks, approximately, are you trying to sync? 2500
• Are you syncing over WiFi or 3G? Wi-fi
• Do you know and can you confirm how fast your down- and upload speeds are on your WiFi network? 1.2 mo/s
• (Optional, for privacy reasons) In which country are you located? France
• Are you syncing local files or Spotify tracks? Spotify tracks
• If you are trying to sync local files, could you try only syncing Spotify tracks. Is this slow? Yes.
• Please provide a couple of examples of playlists or tracks that are slow to sync.
• On the "slow" device, did you:
  reset the cache of your Safari app? Yes
  un- and reinstall the Spotify app? Yes