The "Polysynth" sound, with at least two staves, and a sufficiently long note, causes sound cracks
2.1 version 871c8ce/ Windows10
1) New score for two flutes -> Finish
( the test file is attached after step #5 )
2) In second flute: enter a D whole note, and hit "+" (for tie) one time
3) Skip the third measure -> enter again D whole note in measure 4, and hit "+" three times
(important, two times, and there is no more issue, unexpected but it is so. )
4) In top staff, measure 7, enter a sequence of 16th (with same note, D, important, too), let's say more or less three measures.
So, this configuration:
5) Hit F10 -> for second flute, change the sound: after click on the dropdown list, type Po, to get immediatly "Polysynth" sound
- The test file at this step: Polysynth.mscz
6) Close mixer, and Launch playback
Result: from measure 8, and next, you hear unpleasant sound cracks.