First, a shoutout to pvsage for suggesting this app.
Second, you might be asking yourself...what is Volti? From the repo: Volti is is a lightweight GTK+ application for controlling audio volume from system tray/notification area.
I recently installed Volti and ran into a couple of issues and wanted to share the solutions I discovered.
If Volti doesn't run, i.e. no volume icon, drop to terminal and type volti and check for errors. If you see the following error:
[alsactrl.py:__init__:41] can't open Master control for card HDMI, trying to select first available mixer channel
Open the Volti configuration file (/home/<user>/.config/volti) and under the [global] section, change the value for card-index from 0 to 1. Start Volti (using gmrun or Run from the openbox menu) or reboot the computer.
If you prefer to see a value on the volume scale, open the Volti configuration file and under the [global] section, change the value for show-scale-value from 0 to 1. If Volti is currently running, right-click its icon and select Quit. Restart Volti (using gmrun or Run from the openbox menu) or reboot the computer.
Linux User #586672
Come and Die -- Kyle Idleman