FG7 detunes spontaneously

[VintageOrganPlayer]

Hi, dont know why and what the cause is and how to solve
i played some piano (patch 21 NY Grand 6) and the sound detunded itself below some cents of correct shift. after a while & saving project i tried again and get well again.
i cant believe that.
Any ideas?
Thanks.

now again with another set (live mode) over all 8 patches

[VintageOrganPlayer]

the SCALE tune was set to on - i switched to OFF and i will check if occur again