Use the latest version of macOS
Check your sound settings
If you still can't hear sound from the internal speakers after updating your computer's software, check your sound settings.
First, disconnect any external audio devices from your computer. Also disconnect any cables from the USB, FireWire, or 3.5mm audio ports.
- From the Apple () menu, choose System Preferences.
- Select Sound.
- Click the Output tab, then select Internal Speakers. If you don’t see Internal Speakers as an option in the Output window, contact Apple Support.
- If the volume slider is set low, move the slider to the right and test again.
- If the Mute checkbox is selected, deselect it and test again.
- If you still don’t hear any sound, contact Apple Support.
Check the line-out port on your Mac
If the Output pane lists Digital Out instead of Internal Speakers, check the line-out port on your Mac.
First, disconnect any external audio devices from your Mac. Also remove any cables from the USB, FireWire, or 3.5 mm audio ports. Then check to see if the line-out port is lit by a red light. If it is, your Mac might need service.