Kazam finds no audio devices despite USB headset being plugged in and recognized by system

I am running Ubuntu 20.04 LTS with all the latest updates and kazam 1.4.5 'NCC-80102'. When I start kazam it detects no audio devices despite having a USB headset with speaker and microphone plugged in. I have checked in gnome sound settings, as well as with other applications, that both the speaker and microphone are working properly. I will include a screenshot showing that kazam finds no audio devices. When I run kazam from the command line, it gives the following messages:

```
$ kazam
WARNING Kazam - Failed to correctly detect operating system.
/usr/lib/python3/dist-packages/kazam/app.py:145: Warning: value "((GtkIconSize) 32)" of type 'GtkIconSize' is invalid or out of range for property 'icon-size' of type 'GtkIconSize'
  self.builder.add_from_file(os.path.join(prefs.datadir, "ui", "kazam.ui"))

(kazam:5384): Gtk-WARNING **: 12:04:09.825: Can't set a parent on widget which has a parent

(kazam:5384): Gtk-WARNING **: 12:04:09.832: Can't set a parent on widget which has a parent
WARNING Prefs - Unable to find any audio devices.
```