Hi Breaking Dawn,
I once had met a drama therapist who said people successfully calmed voices (as well as images too) by "acting" them out. Essentially, the patient became the director with the help of the therapist and instructed actors on what the voices were saying. The actors used the words and phrases and tones that were in the patient's head. And by externalizing the voices this way, actually calmed them down or in some cases, made them disappear altogether.