In my flat we have poor coverage with WiFi from the router so i use a WiFi extender to create another network. I'm thinking of getting some audio Chromecast's to play music across rooms at the same time but I'm not sure if that will work due to the networks being different?
I don't have any experience with the Chromecast Audio, but I have a regular Chromecast. I have the Chromecast plugged into my TV and connected to a repeater network (different name than the regular network) and I can cast to it on the TV when my phone is connected to either the repeater network or the regular WiFi network. I think as long as the repeater is connected to the main WiFi router then it shouldn't matter. I think it just detects if it's part of the same home network, which both routers are.
I can't guarantee it will work for you because everyone's home setup is different and you're talking about the Audio Chromecast and not the regular one, but from my experience, it might work for you.
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