Just solved it but leaving it here in case someone else is reckless as I was.
It was about resource management, and somehow I managed to miss unloadAsync function whatsoever.
So solution was to keep track of actual Sound object instance, and bind to its onPlaybackStatusUpdate event.
From here it was easy as Status object being passed to event handler actually contains a lot of info inluding
didJustFinish flag. So in handler it is something like:
if (status.didJustFinish && this.playbackInstance !== null) {
this.playbackInstance.unloadAsync();
}
Additional help was reading from another post: https://forums.expo.dev/t/audio-trying-to-update-unmounted-component-on-android/3850