Why doesn't Emacspeak read coming output?

[Parham Doustdar <parham90@xxxxxxxxxxx>]

Hi,
I’m using Mac OS Sierra, with Emacspeak version 45.0.
If I press M-x and then type ‘shell’, and then do something like ‘ls -1’, the output is not spoken – Emacspeak only speaks the prompt.
I’ve tried using C-e o to turn the monitor on, but nothing seems to change.
Is this something wrong with my configuration, or am I understanding this wrong?
Thanks!