I lost the sound!

[RuffRiders]

Hello, I have a MacBook Air and one day I lost the sound all together. I had tried to bring it back from the keyboard but it seems to be locked and cannot unlock it. Then I went to check on the sound in the system preferences and it is not showing anything either. Anybody knows how to fix this? Please let me know when you can. Thanks

 

[stoconnell]

take a look at this thread ..

https://forums.macrumors.com/threads/683430/

 

[RuffRiders]

Lost sound!

I tried it and let it go black 4 times and nothing

 

[stoconnell]

I tried it and let it go black 4 times and nothing

To clarify, is this a Rev A or Rev B Air, and is it still under warranty?