Freezed visualisation

I have a visualisation of actual measurement like:

This works fine.

When I login at a higher login level (admin) the visualisations freeze.
They are displayed but are not updated anymore.

When I logout the visualisations start updating again.

There is no data loss because the trend charts are OK (no interruptions visible)

For as far I can see there are no restriction regarding privileges.

Anybody an idea how to solve this or what is causing this behaviour?