If the headphones are working OK then maybe the [link|https://discussions.apple.com/thread/6388064?sortBy=rank|'switch'] inside the jack port has become 'stuck' and if it is not that then it can be possible there is a board issue with the audio lines. Have a look in the audio settings do you see the internal speakers built-in option?
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If the headphones are working OK then maybe the [link|https://discussions.apple.com/thread/6388064?sortBy=rank|'switch'] inside the jack port has become 'stuck' and if it is not that then it can be possible there is a board issue with the audio lines. Have a look in the audio settings do you see the internal speakers built-in option? It is unlikely that both the internal speakers have simultaneously failed.
If the headphones are working OK then maybe the [link|https://discussions.apple.com/thread/6388064?sortBy=rank|'switch'] inside the jack port has become 'stuck' and if it is not that then it can be possible there is a board issue with the audio lines. Have a look in the audio settings do you see the internal speakers built-in option?