Install volumeicon-alsa by entering the following commands in the terminal:
sudo apt update sudo apt install volumeicon-alsa
Description:
systray volume icon for alsa
This is a lightweight volume control that sits in your systray. This version is compatible with ALSA. Features: * Change volume by scrolling on the systray icon * Ability to choose which channel to control * Configurable stepsize (percentage of volume increase/decrease per scrollwheel step) * Several icon themes (with gtk theme as default) * Configurable external mixer * Volume slider
Homepage: http://softwarebakery.com/maato/volumeicon.html
Version: 0.5.1+git20170117-1
Section: universe/sound