I can imagine that since his way of moving has changed rapidly since the voice went away which might be due to the typical problems of vertigo that this disease brings.

But I personally think he might have some sort of chronical throat infection. Not the type where he gets hoarse like on the SWW tour, but there are tons of different types of infections. And his talking voice always seems to be on the edge of being slightly hoarse and the way he pronounces and tries to push some notes reminds me strongly of when I have a cold and you try to find ways to work around. Also you typically don't really know how your voice sounds when the throat is infected and hence maybe the insecurity when it comes to reaching notes.