Router SOLID MAGENT in AP mode

This is the original diagram

Router INSIDE Ports + DMZ device -->> WAN Port OPN <<--[[OPNSENSE Firewall]] -->> LAN Port OPN <<--WAN Port  ORBI -- Other LAN Port Orbi ->>> Computer

with this diagram the magenta light off but the Iperf3 measure a max of 550 Mbits to traverse the firewall from the computer to the DMZ

while with this diagram

RouterINSIDE Port + DMZ device -->> WAN Port <<--[OPNSENSE] -->> LAN Port Firewall <<-- Other LAN Port Orbi ->>> Computer

with the magenta light on but Iperf3 measure the total throughput of 1Gb Mbits to traverse the firewall from the computer to the DMZ

Nothing is connected in this diagram to the WAN port of the Orbi, but Internet is active, the app confirm Internet online, and speed test work as expected.

The Orbi have also other 2 satellite connected via 5G backhoul and they works well in both the config but the second have little higher throughput.

As mentioned above the Firewall is a Protecli FW6C (64gb Ram) with OPNSense latest.

Firmware version is V2.5.1.16 for RBR and RBSs.

Factory Reset was never done since I have all my config done and working.

Maybe the WAN port have a different behavior in sensing the duplex or MTU, becouse as said above the highest troughout is achieved if the connection is via any od the bridge ports of the ORBI and NOT via the WAN port.