Besides the HDMI connection, the Chromecast needs +5volts DC for power. Included is a USB cord and wall plug for that.
I'm not sure of your setup, but that system has one HDMI
output. You need an input to use the Chromecast.
If you're taking that DVD/Sound system to a HDMI switch or bridge, it may work. How my (and many other) system works:
The A/V receiver has one or more HDMI outputs. It also has several HDMI inputs.
I have the Chromecast in one of the HDMI inputs on the AV receiver. I also have my cable box and a Google TV unit plugged in.
I have my television on the HDMI port for the TV, which can send and receive. All HDMI ports are bi-directional, but your receiver box has to be setup to both send and receive data on the port you're using.
I have my speakers hooked up to the audio output on my AV receiver. I have not tried my external EQ/amp with this yet, but it should work because it only accepts the audio output from the AV receiver, processes it, and forwards it to the speakers. I just had to move some things around while waiting for some cables
As long as I choose the correct input on my receiver, the TV displays the video and the speakers handle the sound.
Kevin O'Quinn, our senior moderator and team leader, happens to be an audio/video expert and does this sort of thing for a living. I've called him in here, because he knows more about it than I do

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