First thing I would do is to restart both the router and the Roku device/RokuTV.
Then I would verify that my router settings are as follows..
2.4ghz band -- Radio On/Enabled and Broadcasting SSID, manually assign channel to 1, 6, or 11 , not "Auto", set Mode/Protocol to b/g/n, and set bandwidth/channel width to 20 mhz.
5 ghz band... Radio On/Enabled and Broadcasting SSID, manually assign channel to 36-48, or 149-161, not "Auto", and set bandwidth/channel width to 20mhz, then increase as necessary depending on connection stability.
Once these basics are out of the way, can begin to narrow down some issues. Additionally, I would try connecting the RokuTV to the 2.4ghz band rather than the 5ghz band after making above changes and see if the connection stabilizes and mitigates issues you are having.
Feel free to post back with an update or if you have more questions.
Roku Community Streaming Expert
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