RBK20 Connection lost on ethernet backhaul

[Bernhard42]

#Situation
In my Setup (RBK20= 1xOrbi-Router-RBR20 + 1xOrbi-Satellite-RBS20) the wifi work, but some (not all) devices lost communication (irregular) if they are connectet to the satelit RBS20.
I must use ethernet backhaul, it is too far for wifi daisy chain.
Web Interface of RBR20 show >> Backhaul Status=good / Connection Typ=wired.

Hope for info if my current setup is correct or wrong, and if an additional RBS makes sense.

#Connection
>> Cellar: Router=VDSL Modem
(ethernet cabel: modem too switch)
Netgear Gigabit Switch GS108
(form switch, ethernet cabels CAT6 zu different floor. Connectet to RBR20, RBS20 AND other netwerk devices)
>> 1 Floor: RBR20 / V2.7.3.22 / Mode=AP / IP Adress= get dynamically from exiting router / Enable-Daisy-Chain=ON
(ethernet kabel on socket "Ethenet" not the yellow "Internet")
>> 2 Floor: RBS20 / V2.7.3.22

#Is this better / correct?
>> Cellar: Router=VDSL Modem
(ethernet cabel: modem too RBR20)
RBR20 (socket yellow "Internet" to Router, socket "Ethernet" to swicht)
(ethernet cabel: RBR20 too switch)
Netgear Gigabit Switch GS108
(form switch, ethernet cabels CAT6 zu different floor. Connectet to RBR20, RBS20 AND other netwerk devices)
>> 1 Floor: RBS20
>> 2 Floor: RBS20

[plemans]

If should go 

Modem/router------>RBR20----->Switch----->RBS20

The gateway needs to be direct wired to the rbr20's wan port and then the rbr should be connected to the switch via lan port. 

Also, do you have your gateway in modem only/passthrough mode? Or the orbi's IP address put into its dmz? Or the orbi in access point mode? 
otherwise you're in a double nat. 

[Bernhard42]

Thanks for the quick reply.
Currently the modem provides DHCP, the RBR mode is set to AP (access point).
All netwerk devices and RBR and RBS receive there IP's from the modem-DHCP range. This looks good.
I will follow the suggested setup and put the RBR in front of the switch and try it with another RBS.