Make sure the 2.4 GHz radio has all three modes enabled. That would be B/G/N. With some routers, and for no known reason, if the mode is only set to G/N the Roku has issues connecting. It doesn't happen with all hardware, as I don't have issues with my Comcast modem. But because of other issues I had with the modem I placed it in Bridge mode and installed a separate Linksys router as my firewall and all my connection issues went away.
Dan
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