I don't really understand the need for these streaming boxes given that anybody who would have an expensive Sonos device will surely have a TV that has all the bells and whistles.
The only reason most will buy it is it will allow you to add front left and front right speakers into the mix, so you'll be able to have 4 era 300's running. Pretty expensive setup but people have been wanting it for ages without wanting to go down the wired route.
I assume there's hardware limitations currently or they don't want to risk dropouts etc and this will help eliminate it all, especially as all speakers can communicate wirelessly with the box as well.
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