Performance, playback, and autosave problems. MuseScore 3 is making me upsetti.

So, I'm writing a show for a Marching Band. It's both percussion and wind parts, as follows:

Piccolo
Flute
Clarinet
Bass Clarinet
Alto Saxophone
Tenor Saxophone
Baritone Saxophone
Trumpet
Horn in F (Renamed as Mellophone)
Trombone
Euphonium
Tuba
Electric Piano
Electric Bass
Marimba 1
Marimba 2
Vibraphone 1
Vibraphone 2
Xylophone
Glockenspiel
Percussion
Snare Drum
Tenor Drum
Bass Drum
Cymbals

Although there were separate staves for the mallet parts, the Flute, Clarinet, Alto Sax, Trumpet, Trombone, and Euphonium parts were all on one staff per instrument. And even though it still sounds like a lot of instruments, I've dealt with scores in MuseScore 2 where there were separate staves for each different part, like Flute 1 and 2 or Trombones 1 to 3.

Anyways, when I was playing it back, it was very stuttery and simply impossible to listen to. The problem remained when I allocated more of my CPU to it. It would happen when there were only 5 instruments playing. And sometimes, all instruments would play and it would be fine. Anyways, I tried to ignore it and simply wrote the show without listening to it a whole lot. I get 29 measures in, mind you this has taken about 5 hours to do, when all of a sudden the stuttering becomes more consistent than my breathing. It wasn't on and off like before. So I opened up another big score to see if the problem was happening there. Upon playback, MuseScore crashes, which I don't blame it for. I had two big scores open. However, I open my score back up, and I've lost the last 20 measures of work. Those 20 measures don't sound like a whole lot, but it took the majority of my time, about 4 hours. Every single instrument except for Auxiliary Percussion played during those 20 measures, and there were about 5 different melodies going on, along with the drumline parts, meaning the work I lost is irreplaceable. The worst part is that this shouldn't even have happened. I had autosave on at once per minute, so I should have only lost one minute of work. But I lost four hours.

MuseScore 3 was not ready to be released. I've never had any of the aforementioned problems. And I had all of them in one day. MuseScore is up to date. There were no other programs running. In Task Manager, MuseScore 3 was and is set to High priority.

Let this be a lesson: Don't trust autosave. Save every once in a while.