Polysynth sounds different after exporting score

Polysynth seems to play two notes instead of one when exported into a .ogg file. I was unable to confirm whether or not it works the same way with other formats because MuseScore started crashing on startup before I could do so. Going off of what I managed to try before that occurred, it seems to happen consistently every time.

The attached files are the same score, which contains a single polysynth note, as a .mscz file and as a .ogg file.

Update: The same thing happens with .wav and .midi. Also, when you reimport the file back into MuseScore, it's the same as the original .mscz file.