This isn’t a Plex issue per se, but it shows the fundamental need for control over some of the backend tasks. And as I mentioned before, the low volume issue has plagued PLEX from the outset, and allowing configuration of downmixing would be a huge leap in fixing that issue: Let's finally solve the low audio issue please
And as you mentioned you have an ARM device, my device we x86, so no, it’s not an architectural hardware issue, it’s a software issue.