OS: Ubuntu 22.04.1 LTS, Arch.: x86_64, MuseScore version (64-bit): 3.2.3+dfsg2-11 (Ubuntu impish/amd64), MuseScore build number not set, revision: d2d863f

Background: Two days ago, I had not trouble, but then I wanted to play only certain voices, so I muted the other voices in the mixer. When I was done, I unmuted the voices.

Problem: Only the notes I click on and the percussion staffs play during MIDI playback. To be clear, I am not saying that I have to enable other voices in the mixer. The voices are enabled. The play button is greyed out when I start the program. When I click on a voice, that voice and the percussion will play, but nothing else. If I click on any other voice, any of the voices I click on will play, but not voices that have not been selected up to that point.

Furthermore, when exporting the midi will only export the top staff and the percussion. In other words, when exporting to any format from the midi sound, only the top line and the percussion plays.

I initially believed that the problem might be with my system, but new files play back just fine, so I am confident that some setting has gotten switched.

What I have already done

1. Deactivated and reactivated all voices in the mixer
2. Checked that a soundfont is installed, and that it is the default
3. Changed and restored all mixer settings
4. Reset to factory settings
5. Uninstalled and Reinstalled Musescore