Remember this thread?
One more interesting finding :
The noise occurs only when WiFi is on.
Whenever I heard the noise, I could make it disappear just by turning WiFi off.
And the noise immediately came back when turned on again.
(On the other hand, turning on/off mobile data didn’t do anything.)
I never understand what this means, do you? 
Maybe due to system and apps’ background updates when WiFi on?
This might be an odd question, but does the problem persist after following the steps from here: Note 10+ audio crackling and distortion - Page 3 - Samsung Community
Go to: SETTINGS
search: RESET NETWORK SETTINGS
enter: RESET NETWORK SETTINGS
enter: RESET SETTINGS (RESET ALL SETTINGS TO THEIR DEFAULTS)
enter: RESET SETTINGS
Unfortunately, no…
Anyway, thanks for the link 
Now I think this issue may have something to do with the
AAudio API itself, not FMOD.
(But not sure if it’s Samsung’s or Google’s fault. Also, it may be only my device.)
I unzipped this app’s APK file and had a look at it, but no FMOD related files, which means they are using their own engine or something.
The app also has the AAudio API option.
When I heard the noise within my app (which uses the FMOD API), I switched to the app above and had the same tests with it.
The same noise appeared and disappeared depending on the WiFi states.
Do you know any other Android apps which use AAudio but do not depend on your API?
I could test those too and let you know how it goes with them too.
Btw, unlike the question you linked, I never faced any issue with other casual players like YouTube app, YouTube Music app, Google Play Music app, and a video player called MX Player.
Also, no problem with games so far personally, because Unity rarely supports AAudio yet, thus most of the Unity games still use OpenSL ES…
I think the best thing would be to see if the issue happen when using aaudio with oboe tester - GitHub - google/oboe: Oboe is a C++ library that makes it easy to build high-performance audio apps on Android. - oboe tester is in apps folder.
If it it reproduces there (particularly if it happens with wifi and doesn’t without wifi), submitting a bug to oboe will hopefully lead to a fix as they are in a better position to help address something like this. The tester app also has a lot of configuration options, so it might also be easier to isolate the issue there.