It seems to be related…
Digging into the thread I found Odroid N2 test builds
Therefore I tried MicroUSB for the DVB sticks (with powered HUB) – first tests shows that it seems to work. Tested 4 simultaneous clients on 3 DVB bouquets.
In the test build from 20190708 DVB did not work at all (USB3 or MicroUSB).
I’ll give an update if something changes.
Thank you for the clue.