I was also thinking mania, so maybe bipolar? I think there's such a thing as bipolar with psychotic symptoms, which could include hearing voices. Maybe try asking on the Bipolar subforum? If doctors can't get your diagnosis right, then you're probably not getting the right treatment. Could you try getting another opinion?

Also, I have OCD, though my biggest issue is generalized anxiety and panic disorder, plus some depressive episodes. My T and p-doc will sometimes try to pin things on the OCD that I don't think are really it, though there is a lot of overlap between anxiety and OCD. I think sometimes once they think you have a diagnosis, they try to pin everything on that, rather than considering it could be something else instead of or in addition to your primary diagnosis. Which is why it might help to see someone new.