How to Turn Off Voice on a MacBook
The MacBook comes with Universal Access, which offers extra features for the visually impaired, hearing impaired and handicapped. One of the features of Universal Access is the VoiceOver Utility, which basically uses a computer voice on your Mac to tell you where you are on your computer by identifying windows, applications, warning messages and even website links. If you don't need it, VoiceOver can be a very irritating feature but is also very easy to turn off.
Click the "System Preferences" icon in your Dock. If you don't have System Preferences in your Dock, you can also access it through the "Apple" menu or your "Applications" folder.
Click the "Universal Access" pane, located under the "System" heading.
Select "Off" under the "VoiceOver" heading. This will turn off the voice on your Mac. Close your System Preferences.