No Bandwidth usage of sub-servers

Hello.

I am using Virtualmin inside Webmin and like to use the feature Bandwidth Usage Graph. So I configured Apache to place the log files to the "right" paths and it shows data for alle Servers.

However, I have some users managing more sub-servers and only the main ("parent") servers are shown with content. It seems like the traffic of all sub-servers are merged and shown as the traffic of the parent server.

So, when I view the "Parent and sub-Servers" tab, there is less traffic for the parent server than in the summary view. All the sub-servers are listed BUT they show no graph, no limit and "0 bytes" as usage.

Is this a bug or did I configure something wrong?

I am using version 3.47.gpl in master admin mode.

Thanks, Michael