Chromecast is fundamentally simple and powerful. The price is amazingly low but that does not mean it lacks functionality. To me, it simplifies the smart TV model by putting the "smart" elsewhere. In this case it is your device which could be a laptop, phone or tablet. Because of Google's weight behind it, it already has ton of apps who support it.
So how am I using ? Simply put I'm using it in two cases.
This is straightforward and this works fine out of the box. Connect your Chromecast and follow instructions on the screen.
This needed some additional hardware. Buy this Audio Extractor and it will extract audio from the HDMI. It does not require any separate power source. Any now you can attach this to any speaker.
Now I have 4 such setups on different Chromecast devices. My speaker collection is a mix of cheap devices and some better speakers. For couple of my rooms like the kitchen, I am using a cheap Logitech Z120 Stereo Speakers which works fine simple audio. This does not so advanced things like the same audio in each room, although given that the API is open, you can write an app to do that.
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