Need Help Patching A Sound hack if added to workspace??

Theres nothing wrong with this, however, if someone hacks, they won't only inject into workspace, thus you'd have to link the event to every instance in the workspace.

Your issue however is that you're trying to set the parent to nil while something else has set the parent to workspace in the same tick. add a wait() and it should work.

another thing to mention: PlayOnRemove value should be set to false to make sure it wont play.

workspace.ChildAdded:connect(function(Object) 
	wait()
	if Object:IsA('Sound') then 
		Object:Stop() 
		Object.PlayOnRemove = false
		Object:Destroy() 
	end 
end)