Score playing back as the piano rather than the actual instrument.

So basically what is going on is that whenever I play back the score all of my parts just play back as a piano. The snare drum and percussion play back as a piano too and its really messed up and I don't know how to fix it. It started happening after I updated my muse score to the latest version. I kept on pushing to update it later for quite a while so today I just decided to get it over with. I had muse score open while I was updating it so I don't know if that changes things. Another point to mention is that only the scores I had open were affected.

Can someone please help me because I spent a ton of hours working on a piece, and I dont want to restart just over a stupid bug.

Thanks!

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