I tried it there on mine and it works.
My first questions would be
They've been pushing a new upgrade though, have you taken it?
Is it a problem with all music or just a few?
and my first suggestion would be
Maybe you're in an area/have a computer setting where spotify is not able to download music, i.e., if you're at work they might have a spotify block-mognify-er that's only half working (i.e., not blocking stuff that already downloaded, but filtering new stuff).
I got 1c from spotify last year; you're talking to a professional musician.