Wobble is a voice movement that indicates dysfunction. It appears when there is improper balance between muscle systems, with the “chest register” dominating all adjustments. There is subsequent heaviness due to muscular overloading. A wobble sort of mimics vibrato, but is slowed down by the heaviness - like a thick jump rope that is hard to swing around.
Other negative symptoms will accompany a wobble, such as shaking the jaw or head, constriction in the throat, and problems with pitch.