[MU4 Issue] First notes missed in playback; spurious notes during playback and at end.

[rgreen5]

Describe the bug

Play back the attached score. Make sure that Muse Sound choirs are activated in the playback setup (View). Listen for any playback effects that do not match the written score.

dowland_all_people.zip

RESULT: The first chord is omitted during playback. There is a wrong note in the soprano voice after several of the quarter notes (crotchets). At the end there is a spurious note added.

Expected behavior

Playback should match the written score.

Platform information

OS: Linux Mint 20.1, Arch.: x86_64, MuseScore version (64-bit): 4.0.0-223120419, revision: github-musescore-musescore-4006440

[SteveBlower]

I found this problem occuring only with imported version 3 scores. Once saved from version 4 the problem disappears. Is that your experience also?

See #14387

[Tantacrul]

Same question as before @rgreen5 - are you still experiencing this? If not, please return to it once we've made an announcement about merging our large performance issues and let us know if this goes away. It'll be really helpful!

[rgreen5]

OS: Linux Mint 20.1, Arch.: x86_64, MuseScore version (64-bit): 4.0.0-223300405, revision: github-musescore-musescore-88bcaae

Better. No wrong notes and no extra note after the end of the score. Just the sound lag, which is also covered by #14716.