My wife could not hear audio today when she was viewing YouTube videos in the Firefox browser. She thought the problem occurred after the automatic update of Windows 10 on her system with the Anniversary Update. The YouTube audio setting was not muted and was turned up to a level where I should have heard sound and I found that I could hear audio for a music file outside of Firefox and I could hear audio for the YouTube video she was trying to view within the Microsoft Edge web browser on the system. And when I went to the CNN website, I was able to listen to the audio associated with a news video on the site.
The Browserspy website's Adobe Flash Information page showed the version of Flash installed on her system was 23.0.0.162.
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