Why is my Chromebook CB3-431 not playing any audio?
SYMPTOMS
One or both speakers may stop working on the CB3-431 Chromebook due to an issue with a Google audio driver codec.
SOLUTION If you experience this issue, please
contact Acer support to create a repair order resolve the issue.
MORE INFORMATION
A new Chrome OS update (Chrome OS R64.10176.0.0) will be available soon that will prevent this issue from occurring.