How to efficiently replicate sound changes to all clients?

I’m currently adjusting the PlaybackSpeed of a Sound (vehicle engine sound) relative to the RPM of the engine, however, I’m making these changes on the client so others can’t sadly hear it.

I need all the players to hear this sound, I could play it and manipulate it on the server but that would probably sound terrible and would load up the server. What method would you recommend?

Well, if you wanted to you could use a RemoteFunction to tell the server that the RPM has changed, then the server will broadcast to all clients using a RemoteEvent that a players RPM has changed. However, you could do this on the server, and won’t really load-up the server. You’re saying probably, as-if you have not tried it?