RBR350: 50% download speed over WIFI, upload speed is 100%

Hi,

We have a 100/100 fiber connection in our house, in the basement there is a fiber converter that hooks straight into the Orbi router. (No ISP modem with built in WIFI or anything like that)

When running speed tests on my wired connections i get the full 100/100 both when running straight through the router and when running through a satellite using wired backhaul, but as soon as I go through WIFI, my download speed is cut in half while retaining the max upload speed. (Tests done next to the satellite/router, no walls interfering etc)

I have attached an image showing the current connections and their relation as well as results from speed tests (dotted lines are WIFI connections, filled lines are wired connections)

Conditions:

* We live in a very small village and have no interfering WIFI signals surrounding our house.

* Router and satellite are updated to last firmware.

* IPv6 is disabled

I have so far tried the following without any difference:
1) Change 2.4GHz channel from Auto to all the others.

2) Made sure the default MTU size of 1500 is correct (by pinging with larger packet size until they are scrambled etc)

3) Disable the 20/40 MHz Coexistance

4) Disable UPnP

What is next?

EDIT: My image isn't showing up, attached it as a file as well.