Dump in : https://pantheon.corp.google.com/storage/browser/chromiumos-test-logs/bugfiles/cr/822762

Could you attach chrome:media-internals info? Copy all from the "Players" and "Audio" tabs.

Players tab added in the Link at #1, and audio tab is just empty. also attached a screenshot.

+some people from the "no audio" team. Do you know how to get those neat text logs we get with customer feedback?

You'd have to do a Hangouts call. Maybe some basic tests here is in place. Have you checked the console output for example? Could this be the gesture requirement?

Uploaded both the logs during an hangout call, In-fact, during a hangout call there this problem does not raises. (we already have a user-input in the view, so call goes successful, there is audio).

If you use webaudio without an active user input, It fails (ex: test.webrtc.org) or the sample page given in the initial description. 

I think the root cause is because of the javascript error in few test pages. 

Javascript error: The AudioContext was not allowed to start. It must be resume (or created) after a user gesture on the page. https://goo.gl/7K7WLu

As Ravi mentioned it is not affecting any other webrtc apps.
  
Fix for this https://github.com/webrtc/samples/issues/1028 ticket should resolve it. This github issue has all the three sample pages which are affected by this issue. 

Tested in 66.0.3359.48 beta and works fine. Closing.

and I can't close the issue (unable to change the status)

66.0.3359.67 (Beta M66) the issue present again. can you please check Its backported into the upstream ? 

#12 Same in Windows as well. 

Beta 66.0.3359.46 /10452.19.0 Windows 7 (Thinkpad lenovo), Windows 10 (Asus UX430x)