Not everyone that handles Disability cases is a lawyer, and the rules of the Social Security Administration allow that. Contact the State Bar Association to make sure that he is a lawyer.
You know that repeated phone calls do not work. Have you written a letter? In the letter, state that you are unhappy and that you do not want him as your lawyer any more. Give him a deadline of ten days, for example if you write the letter on April 12, state "Please provide your written reply on or before April 22, 2012." Make two copies of your letter and hand deliver the letter to the receptionist. Have her sign and put the date and time that she received the letter and return it to you. You will now have a copy and a copy that will be a receipt.
I hope this stimulates the action that you seek. Good luck.
No attorney-client relationship has been established because of the information provided. Seek local counsel to address your particular facts. MJHJ