Did the Wi-Fi analyser show any other hubs/APs on the same 2.4GHz channel? Were they strong - more than say -70dBm ?
have you tried using a different channel, keeping to 1, 6 or 11 ?
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I know a bit about Wi-Fi, Telecoms, and TV as I used to do it for a living but I'm not perfect so don't beat me up... If you make things you make mistakes!