
This morning, I was unable to hear the sound in the
youtube videos. There was no wrong with my audio driver, sound was on in the YouTube Video Player. What went wrong ? Couldn't think of anything that might have changed the things.
Did some
Google and finally reinstalled my
adobe flash player and it worked like a miracle ! Sound is back.
Uninstall adobe flash player
Restart your machine
Install latest adobe flash player
But there might be other reasons too for which you might lose the sound of youtube or such embedded players. e.g. problem with your sound driver, or you might have reduced the volume on YouTube Video Player ... etc
This Google
support page might be useful for you.