I'm still lurking...
All the tracks have 'Chords' mode active.
While there's no actual 4 note F#m7 chord, but there is an E, F# and A on the cello track. When I switched the chord mode off and back on again, using "syncronize... first" the notes were transposed to only include notes from a D maj chord.
So that's the fix. Since it's possible to edit notes in this mode they can get out of sync with the chord track. Doubtlessly, there are other workarounds as well.
Would have been nice for you to have actually said which track of the seven your question was about, instead of "one of em" but I managed to find it just the same. Maybe next time.