Ex2 Ultra standby not working with 5.20.113

After the latest firmware update to 5.20.113 the Ex2 Ultra NAS does not go into standby anymore. Fans are running all the time and also disks. How can this be fixed?

@G0ldmember Check your admin UI Dashboard for Indexing and or Generating Previews.
The articles listed below will help.

https://support-en.wd.com/app/answers/detail/a_id/29479
https://support-en.wd.com/app/answers/detail/a_id/29836
https://support-en.wd.com/app/answers/detail/a_id/30048