We can add a fix for this in 6.10, however a workaround for you is to Stop the array and then edit the file:
'config/shares/domains.cfg'
find this line:
shareUseCache="prefer"
and change to:
shareUseCache="no"
You can edit the file by navigating to it via 'flash' share on your network, or open Terminal window and directly edit on the path:
'/boot/config/shares/domains.cfg'