If you can’t hear your Mac speak
If your Mac doesn’t speak, you may not have selected anything for it to speak, or the volume might be turned down. Here are some solutions to try:
If you want to hear selected text, select the “Speak selected text when the key is pressed” checkbox in the Speech pane of Accessibility System Preferences (choose Apple menu > System Preferences, click Accessibility, then click Speech).
If you want to hear alert messages, select the “Enable announcements” checkbox in the Speech pane of Accessibility System Preferences (choose Apple menu > System Preferences, click Accessibility, then click Speech).
Make sure the output volume is turned up in the Output pane of Sound preferences or use the sound menu in the menu bar if it’s visible (choose Apple menu > System Preferences, click Sound, then click Output).
If you use VoiceOver, make sure it’s on. Press Command-F5. If you don’t hear the VoiceOver greeting, press Command-F5 again. If you still don’t hear the greeting, check the volume settings. If you’re using a portable Mac, you may need to press Fn-Command-F5.
If you’re using an app that speaks to you, check the app’s preferences to see if you need to select an option to hear the app’s messages.