The phenomenon of hearing intelligible voices or noises in meaningless background noise is known as “auditory pareidolia.” The sources of this noise vary; they may include electric fans; running water; airplane engines; the hums of washing machines; or white-noise machines, according to audiologists. It is an auditory sub-type of pareidolia, in which people see faces or other meaningful patterns in ambiguous images.
If you build it, they will come.