I was reading a "getting started with REW" a step by step guide, where starting on page 7 of the 132 page article, it describes using either an HDMI connection or the 3.5mm headphone output. I'm thinking the HDMI would be much easier to use configuring a 7.1 system.

https://www.dropbox.com/s/zdhq72a1puyyxpr/REW%20101%20HTS%20Current%20Version.pdf?dl=0
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