i am not using ubuntu, but there are some common command can help you. e.g. "ps" can list all running processes.
you run the "音效設定" and type "ps -Af" in the terminal, it will give you some hint about what is "音效設定". i found that quite useful, for example, after i installed "scim", but i am not sure if it is running, i can type "ps -Af | grep scim". if scim shows up, it is working.
back to your problem, yes, please type "pavucontrol" in the terminal, a window will show up, it won't hurt. if it say pulseaudio is not running, you are not using pulseaudio, try other program. |