spotify premium playlists disappear and fail to show as cached on iphone4

[kingspears]

Hi, I have been having issues with the offline mobile sync - when I access for the commute each day, my most recently added and offline-synced tracks take a couple of mins to reappear, and when they do, they are no longer cached for offline. Curiously, older tracks in the playlist show by default; some of these are cached from months ago. This is really frustrating - any help or advice greatly appreciated! Thanks, Danny