The track you have selected is no longer available for play

Explanation:

The track you are trying to play is physically no longer available for playback. It means the music file has been deleted, moved or renamed. 

Solutions:

• If you are using Lightning Server, please go to Music Library setting page, click 'Rescan' to let Lightning Server recreate the index of your music library. After the index is created successfully, select 'Refresh Cache' if it does not start automatically so the Lightning DS can update the album information stored on your iPad.
• If you are using 3rd party UPnP/DLNA Server, please proceed a rescan on your server management software, then select 'Refresh Cache' if it does not start automatically so the Lightning DS can update the album information stored on your iPad.