Restarting iTunes Match DOUBLED the songs I have...

I had Match turned on for quite some time on my iMac, but turned it off a while ago.

When I upgraded my iPhone to the new iOS, all my playlists were wiped out on my iPhone.

So I turned Match back on, on my iMac - and suddenly I had DOUBLE the songs on my iMac. Most of these songs have the cloud with the arrow coming down next to them - which means I haven't downloaded them yet.

All of these are duplicate songs which I already have on my iMac (they are my songs I purchased either from iTunes or elsewhere).

So now all the playlists on my Mac are messed up with duplicates, as is the entire library.

This only happened with the songs that I'd already uploaded. Tracks that were never uploaded in the first place have not been impacted (there is only one "version" of this song - the one I put on my iMac locally).

Any input as to how I can get rid of these duplicate tracks? (outside of manually deleting them, lol) would help. I have over 36,000 tracks on my iMac, and have received the "too many songs" message as well.

Thanks in advance, Craig