One of my ticks is whistling. I found, purely by accident something that gives me some relief. I don't now if it would work for other vocal ticks or not but here it goes.
Take something small, like one of those glass coffee stirs or a pencil eraser something about that size. Gently put it inside your mouth between your upper lip and your gum.
I think the official term for that part of your mouth is called "Superior labial frenulum - http://theslowdog.com/wp-content/uploads/2011/02/Oral-Cavity1.jpg
A gentle pressure there and the urge just goes a way and I feel very calm. Sometime