The only time I have had this problem was during the worse times of stress. The last time I had it was when I was in a job and trying to learn the switchboard. Talking on the phone is bad enough! Most of my really tough problems have been job related.
I would twist my hair and pull it out.
After I left that job (for a better one) I did not have any further problems. I suppose you could say a change of environment helped. I don't know if this helps, if not, please disregard.