Install aumix-common by entering the following commands in the terminal:
sudo apt update sudo apt install aumix-common
Simple text-based mixer control program (common files)
aumix is a small, easy-to-use program to control the mixer of your sound card. It runs in text mode using the ncurses library, or from the command line (non-interactively). It can read default settings from a file, and it can also automatically save and restore the mixer settings at shutdown and boot. . This package provides files common to aumix and aumix-gtk.