Unable to Play track

[sfelix1]

I know this problem has been posted, but I have tried everything suggested and still have had no success.  I start playing  from my playlists.  Some songs play with no problem.  Then another song will start playing, only to stop halfway through and give me a pop-up window stating, "unable to play track".  I have also had songs just stop in the middle and skip to the next track for no reason.  I have been using Spotify for quite awhile and this has started happening about 2 months ago--yes, I have been trying to solve the problem myself.  I am tired of my music stopping.  I teach fitness classes and rely on my music.  I can't have songs stop playing in the middle of my sessions.  Things I have tried:   I have uninstalled spotify on my computer and on my iPod.  I have cleared history and cookies.  I have deleted all old playlists.  I changed my music quality to normal.  I have reset all my internet connections. 

I have an iPod touch5, 7.1.1.  I have approximately 100 playlists, and about 7 are synced for offline.  I think my mobile spotify version is 1.1.0.2549.  And desktop version 0.9.10.14.g578d350b.  My provider is Time Warner Cable, USA. Username: sfelix1

If this does not get resolved in the next 2 days, I will be cancelling my premium subscription.  I have been putting up with this for 2 months and I am a premium user. 

[Peter__]

Do you have any local files imported into your desktop client (in the local files tab on the left)?

[sfelix1]

Yes, all my music that's on my computer and itunes.

[sfelix1]

Since I do have local files imported into my desktop, will this cause random tracks to stop playing?  Even tracks that are not in my local files?