They will work, altho you are slightly wrong identifying the jacks: The left column is HD component out (red, blue, green from top to bottom) while the next column (white, red, black) are stereo left and right, and coax digital audio.
Use the stereo outs and you should be in good shape.
Note that the box might have audio-out options, such as fixed volume versus variable: You can control the volume of the stereo outs with variable output, just make sure you don't pooch the other audio such as digital or hdmi.
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