The trouble shooting techniques posted do not necessarily work. In my case, to prove how no network issues are prelevent, I can screen cast to my Roku from my phone the Roku app running on my phone attempting to connect via IP address without success.
In addition, I have cleared both my app data and cache. I have set both screen mirroring to both default and permissive, which in itself makes no sense in terms of difference to users. The problem has to be with the app. I have 3 other Roku devices that do connect.
It's been about a week since I've tried it, but I could cast to my 4800 without an issue from my iPhone XR. The Roku is hard wired to my network, but most of my other Roku players are WiFi, and they all appear as a destination for screen mirroring. Some are connected at 2.4 GHz while others are on 5 GHz.
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