If you have a Roku device that supports 2.4 GHz only, be aware that Comcast and other ISPs have started changing the 2.4 GHz settings to only support 802.11 g/n, rather than the traditional b/g/n. That causes issues with Roku devices.
If that's the case, change the settings to b/g/n. Or, get them to.
If your Roku device supports 5 GHz, ensure there is a sufficient 5 GHz signal reaching the device.
DBDukes Roku Community Streaming Expert Note: I am not a Roku employee.
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