Simple audio monitor made with GStreamer, Flask and websockets.
Besides the dependencies listed in the requirements.txt file you need the GI Instrospection packages for GStreamer, GLib and Python.
If installing under a virtualenv you may need to use the '--system-site-packages' flag so it picks the GI bindings.
Running audio_monitor.py will start an http server on port 5000 displaying the levels for all the detected interfaces. It detects new devices and handles disconnections gracefully.
There's another tool, list_devices.py that only lists the detected audio devices and, optionally, can keep monitoring for changes.