Found temporary solution. When I install pavucontrol, there I am able to switch sound output on running application (including firefox). But later when I change setup (turn on or off my TV) then I must do it again this way.
Therefore I am unable to control my sound output using built-in sound controls in ubuntu (gnome) desktop and only possible way is to try another applications. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1910387 Title: Firefox don't respect sound settings. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/firefox/+bug/1910387/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs