Song on Mobile plays different version than song on Desktop

[jfullam]

I recently started a Premium 30 day trial. Downloaded the Spotify desktop program and created a beefy playlist.  One of the songs I included in my playlist was "Build me up Buttercup" by the Foundations.  When I play it on the desktop, it sounds like the standard classic tune I've known all along. Yet when I play the tune on my iPhone, it seems to play some odd acapella version. Definitely not the same tune.   What's up with that?  Can I correct this?

[bschafrath]

I have quite a few AC/DC tracks on my PC from several of their albums. Alot of my playlists have these songs in them.

When I go to play them on my iPhone, either it won't play them or it substitutes for either a cover band (Which sounds awful) or a kareoke version of the song, which is just horrible.

It plays just fine on my PC. When I control Spotify with my phone through the PC it plays just fine. When I play on my phone, the songs revert back to a non AC/DC form.

I even downloaded all of AC/DCs songs onto my phone. I can play them through iTunes, but not through Spotify.