I don't really know if playing sounds/music and GetLocalPlayer can cause desyncs, but you could try playing the sound/music, setting the volume to 0%, and if GetLocalPlayer () == yourParticularPlayer, set the volume to 100%. But, I don't really know if that is desync-proof
I'm on a page about incorrect corrections, and spent the better part of like two hours trying to get someone to understand that -5^2 = -25, not 25, and then that post had comments get reposted because that group is self sustaining, and that person was in turn trying to explain what I just explained to them. And I'm taking that as a victory