schizophrenia, i believe goes alot deeper than just an illusion. I often get echoes of noises mostly voices when im almost completely quieted in the mind. Alot of times i feel that it is sending the noises to me and that im not just picking up things floating around on another plane, sometimes especially when this neg which i dont think i have a problem with ne more was around me he would growl and laugh insanely all sorts of things. Honestly, you have to be careful whether the voices are being generated inside ur head our outside ur head. my greatest advice is to try to talk back to it, and get a feel of where its coming from