I’m kinda confused as to how you want to make something audible only for one player if in splitscreen everyone shares the same speakers?
Even if you play a sound only for one player (which is totally possible), then the other 3 hear it anyway.
In splitscreen, the only thing I can see being relevant is having the sound play relative to a player’s location. And I just tested that in our splitscreen game:
Sounds next to only one player play correctly on the left/right/front etc., so they are properly relative to the location.
Sounds next to more than one player are calculated out of all location, means if I have a sound left to all players, it’s playing on the left speaker, if I have a sound between them it’s between the players (so both speakers) etc.