RBR50 Wifi disconnecting and slow

[Pweschmidt]

Hi, I already saw a few posts on the issue of connectivity with the RBR50 triband Wifi router. Here's my setup: 

I got a DSL modem from the telecom provider (UK Openreach). From there into a router via ethernet port: Fritzbox 7530 (latest firmware). From the Fritzbox modem via ethernet port to the ethernet port of the Orbi RBR50 router. 

The connection to the network (internet) from Fritzbox is fine. But Orbi drops out frequently and is very unreliable.

As I said I saw similar postings, but not many suggestions as to what you can do. 

[plemans]

The fritz!box that you have is a modem/router combo device. if you're using it in router mode and the orbi in router mode, you're in a double nat and going to have issues. the easiest/fastest fix (but lose some features from orbi) is to switch the orbi to AP mode. This lets the fritz!box to control the routing function and the orbi to act as wireless access.

https://kb.netgear.com/30186/What-is-Double-NAT