Datafield updates more than once a second when Activity is not started!

Hi,

All my own DataFields on my Fenix 6X are flickering (changing what is seen on the screen several times a second).

When I then start the Activity, the flickering disapears.

This does not happen on simulator.

the CIQ Update() function of the DataField is called by Garmin once a second. 

So how is it possible that the screen updates more often.

This can be seen for example on https://apps.garmin.com/en-US/apps/444de4c9-e497-4652-afb6-19d0fb23817b

Any help really appreciated

Marcel