@Richie2x4
A little unclear as to your question.
Are you still using your Cox gateway (traditional dual band 2.4ghz and 5ghz modem/router) or have you switched to a newer 5G Home Internet Gateway (ie. Verizon, Tmobile, etc)?
What is the model number of both the Roku device (from Settings/System/About) and what is the model number of the Gateway you are currently using?
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