Sound just not working

For reasons beyond me, my sound just didn't work when I turned it on today. I've checked, the sound should be coming through my system speakers and will play sounds on other applications, but nothing is playing for musescore. I've checked the sound font and the one that's supposed to be there is there. No instrument is muted or on solo, and the play panel shows the volume about halfway up, but no sound whatsoever is coming out: not when I click on notes, not when I hit play, nothing. Help!