I have a ASUS DSL-AC52U Modem using iiNet NBN and on 3 seperate computers I cannot connect to the 5GHz network, all 3 computers can only find the 2.4GHz network.
-All phones and Xbox's in the house can find and connect to the 5GHz network.
-The modem was replaced (same model) as the previous modem stopped connecting to anything, so all 3 computers were previously connected to the 5GHz network.
-I have tried turning modem/computers off and on, reset modems several times.
-I have tried the firmware version that was already on it, and also the latest firmware version through ASUS' website
-Network adapters suit 5GHz (was connected through previous modem) and enabled.

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