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Both you and tonyl: What model are your RG's? "2wire" is ambiguous, not the specific model-name.
Posts imply ATT reusing rejecting RG's on other customers, and some older 2wire's wireless signal just deteriorating over time (with recommendation even to make it last, by reducing transmit power).
In theory, hope ATT would replace your RG, if its wireless range is defective. Don't know how they judge such complaints.
Haven't used it, HomePlug can extend your network thru house power; instead of trying for one wifi to reach everywhere.