Imagine a MultiplexableSoundToGlobalController with !SlaveFader in the GeneratedEvent field.
Then in the Value field, you could use an expression of the form:
!Live * !MasterFader + ((1 - !Live) * <yourAlgorithmForGeneratingValues>)
That would give you a toggle named !Live to switch between live override and your algorithm. Then you would put this into a Replicator to get multiple !SlaveFaders to control. !MasterFader would be a SpecialValue of the Replicator so there would be only one.