Happy to try to help you guys figure this out, but keep in mind: I rarely use FB (never Messenger) on my phone, I'm "anti-social" like that. Now that I think about it though, a friend and I tried video calling with Hangouts a few days ago and never got through to each other...
I blamed the alcohol
btw I prefer the old fashion in person social events, I don't get this "face" and screens apps things be called social for me is just ways to avoid real personal human to human direct contact. So I don't use most of those app too and don't think I'm "anti-social" but I get that some people think that way regards me, and I don't care after all they are the one avoiding human contact not me I'm very welcome to that...
if you find any solution on this let me know internet here doesn't allow me to use those fancy video apps

I blame it on the politician(the lame internet here after all they are the one that allow this sheettt internet)... :silly:
lol.
Attached is stock mixer_paths..
not sure how to figure out this issue.
you can't compare some featuring of custom and stock, we don't have moto source to build we make our on of course using qcom related but that is not the perfect one, Moto apparently doesn't need to released all thy source so we will never have they audio display media, because of that some things need a lot of work to make it happen.
Don't use moto stock file to compare it will not be successful because we change a little to make things work.
the problem is probably in this section
I can't test this type of thing I don't use those app so test the attached if not good try to play with the files maybe use the
shamu file as example, and maybe is need to change others files like "audio_effects.conf", "audio_platform_info.xml" and "audio_policy.conf"
try the file attached and let me know the behavior, share a log.zip using the log tool of mod
kernel adiutor so I check after...