As the monitor is connected, via an adapter or directly to HDMI ?
What kind of wired network 100, or 1000 ?
Try to reset the bindings on the router.
You need to find the right settings (change the source, to collect the utility of the DTC , test the work).
https://github.com/150balbes/Amlogic_s8xx-kernel/blob/S812/arch/arm/boot/dts/meson8m2_n200_m8s.dts#L568