Muse Sounds: when Violin 1 and Violin 2 play in unison or in octaves, it's out of tune

Describe the bug
When Muse Sounds Violin 1 and 2 play in unison or in octaves, it's not quite in tune. For most notes it's subtle, but it seems like notes with sharps ("black keys") or affected more often than "white keys", and in the attached test score I've marked a few very noticeable ones.

It also seems to matter whether you start playback on a note, or that it is played legato-ish after another note.

Of course, this also depends on the different amounts/styles of vibrato. So probably it's simply not always possible to make them as much in tune as they would sound in real life. But for those few extreme ones, I'm sure we can do a bit better :)

Video / original report (not made by me): https://youtu.be/zJP2XXfwoY4

Test score: Violin 1 2 octave test.mscz.zip

(It might apply to other instruments too; I've only really tested the solo violins so far)