I had some luck here today creating a guest 5Ghz network and connecting my Chromecast to that. Here's the steps that worked for me: Login to the router admin Scroll to the bottom and click the settings icon for Guest Stations Make sure 2.4Ghz is disabled, and 5Ghz is enabled I gave my guest network a custom name and password, but don't imagine this is required Go into Chromecast wifi settings and forget your current network, then connect to the new guest network Connect your other device to the same guest network and see if casting works ... View more