Please make sure that if you have both a 2.4 and 5 ghz network, that you are making sure both the Roku device and your Airplay device are on the same frequency network (i.e. if you have netgear100 and netgear 100-5G, both devices need to be on the 5g or the non-5G one)
this is very well understood but you still haven't explained why on many devices Settings > Apple AirPlay and HomeKit is totally missing from the menu. This has nothing to do with network or user misconfiguration.
Please stop give useless information and give some purposeful feedback.
After a full day of working, I finally found a solution. One article suggested a change in display of the roku stick. I changed 1080 to 4k. Lo and behold my 3810 Roku stick now appears in Airplay mirroring - and works fine. As I write this not, 1 am running videos from Internet on my ipad.
not sure how to find out where to look and change the setting in settings to see if its 5g or 2g. May I suggest some videos for us old people?
On the Roku, look at the network settings (Settings/Network) and see what WiFi channel number it's using. If the channel number is below 12, you're using 2.4 GHz WiFi. If the channel number is higher, then you're on a 5 GHz WiFi radio. Depending on your Roku model, it might not even support 5 GHz. For the current models, only the Stick+ and the Ultra support 5 GHz. There are some older versions of the Premiere that also support 5 GHz, and then some really old ones as well, but they won't get AirPlay at all.
Roku Community Streaming Expert
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