Where is the 5.1 Audio???

As a new user to KODI, I am still in the learning stages. However one thing I am frustrated with is that on my SCHISM TV ANNIVERSARY EDITION KODI 17 (I’ve tried several builds) installed on a new Amazon Fire 4K Ultra HD BOX I just cannot get more than “Stereo” from ANY Stream I can find. I’ve changed the Audio Channel from “2” to “7.1” and still nothing but stereo. Now I know a lot of streams even in 1080 for some reason (What Exactly is that reason?) don’t have 5.1, but EVERY Stream I have tried? Am I missing a setting somewhere? I’ve got the FIRE TV feeding directly into my TV’s Input through ARC, and then the ARC is feeding my A/V Amp…. The Denon Amp displays beautifully the Type of Audio that it is passing, and getting anything above “Stereo” is Standard… Mostly Dolby 5.1 and Above for other sources such as USENET MKV’s…..

Any ideas to what I am missing and not correctly setting up?

Thanks!!!!!Huh