ReadyNAS OneDrive never idle / ReadyNAS 524

ReadyNAS 524 / 6.10.4

I have recently noticed that the disks in my ReadyNAS are getting constant repeating access. Previously, they were quiet and idle at times.

I used 'iotop' and it returned that OneDrive seems to be the culprit:
TID PRIO USER DISK READ DISK WRITE SWAPIN IO> COMMAND
22278 be/4 root 0.00 B/s 3.15 M/s 0.00 % 17.43 % ng-csd -s OneDrive -l 1
...

The open files of that process show the following:
$ sudo ls -l /proc/22278/fd
total 0
lr-x------ 1 root root 64 Jan 18 14:00 0 -> /dev/null
lrwx------ 1 root root 64 Jan 18 14:00 1 -> socket:[2825093]
lrwx------ 1 root root 64 Jan 18 14:00 2 -> socket:[2825093]
lr-x------ 1 root root 64 Jan 18 14:00 3 -> /dev/urandom
lrwx------ 1 root root 64 Jan 18 14:00 4 -> /apps/.cloud-storage/cache/1610218964/fs-cache.db
lrwx------ 1 root root 64 Jan 18 14:00 5 -> socket:[2826462]
lr-x------ 1 root root 64 Jan 18 14:00 6 -> anon_inode:inotify
lrwx------ 1 root root 64 Jan 18 14:00 7 -> socket:[2831125]
lrwx------ 1 root root 64 Jan 18 14:00 8 -> socket:[2850393]
lrwx------ 1 root root 64 Jan 18 14:00 9 -> /apps/.cloud-storage/cache/1610218964/fs-cache.db-journal

I checked the logfile under Microsoft OneDrive -> Settings, but the last activity has been hours ago, so it is not synchronizing anything.

When turning OneDrive off, the ReadyNAS quiets down, but returns to the problem once enabled again.

I tried to reset OneDrive by executing a Leave, deleting all files on the ReadyNAS, and then setting it up again. It took a while to resynchronize, it finished, it was quiet for some time, and then the problem showed up again.

Has anyone else noticed this?