Had severeal issues having the Orbi systyem selecting 5G backhaul.
My suggestion is that you under the menu "Advancwed Wireless Settings" are able to set 2.4G Transmit Power Control lower than 25%. E.g. 10 % or even disabling it.
Anyway, the system seems tobe too sensible to wich backhaiul channel is used.
Jesper
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