For https://samknows.com/realspeed/ to work you need to have the Hub 4 in router mode and not modem mode in case that's what your doing. It won't work in modem mode using a 3rd party router 🙂
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BT Full Fibre 900 FTTP - Asus RT-AX82U to Openreach ONT Box & Asus RT-AX56U with AiMesh setup
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