I think you're going to be a little disappointed if you think simply turning a port on or off will enable/disable a specific microphone "automatically" in any use case. Maybe you'll prove me wrong, but the audio device selected for input in the operating system will not necessarily fail over to the next similar device type that gets turned on. You'll still need to set the audio preferences in the software you're using or the Control Panel, is my guess. And then, there's really no point in turning a port on or off. Just leave them all on and make the selection in the software.
What it sounds to me like is that you're trying to do what a mixer or interface does with non-USB microphones. Why not go that route, and skip the hub, which, as [MENTION=196922]Mack Caster[/MENTION] says, is generally not recommended for audio use.