Playback is not functioning properly.

I don't know how it happened, but the playback on my MuseScore is all messed up. In the attached video, which I hope actually is attached, I'm playing back some notes on what's supposed to be a piano at 120 bpm. All of the notes are really really high pitched and the tempo is way faster than 120 bpm. Has anyone else run into this problem or does anyone have a fix for it?