Ubuntu 18.04.2 Firefox Quantum 65.0.1
There is no sound from Firefox or Opera browsers when playing youtube videos etc. Chrome works fine. Desktop music/video player apps also work without any issues. Neither inbuilt speakers nor headphones work for the problematic browsers.
I've gone through the other posts that reported the same problem and tried all the solutions; didn't solve the issue.
- Pulse-audio is installed by default. Firefox and Opera show up in the list of applications under sound settings with their respective volume control though.
ubuntu-restricted-extrasdidn't help. I don't think it's a codec issue. Playing ogg/flac from wikipedia also makes no sound on firefox.
- Clearing cache as mentioned in firefox faq didn't help either.