What 3rd party devices are supported?

Volumio born as open-source OS.

The first compatible and most performant 3rd party platform is Raspberry PI.

There are Volumio images available on www.volumio.com for the Raspberry Pi and these are the compatible models:

Raspberry Pi 1 Model B (RPi1B)
Raspberry Pi 1 Model B+ (RPi1B+)
Raspberry Pi 2 Model B (RPi2B)
Raspberry Pi 3 Model B (RPi3B)
Raspberry Pi 3 Model B+ (RPi3B+)
Raspberry Pi 3 Model A+ (RPi3A+)
Raspberry Pi 4 Model B (RPi4B)
Raspberry Pi Zero (RPi0)
Raspberry Pi Zero W (RPi0W)
Raspberry Pi Zero 2 W (RPi0W-2)

Raspberry Pi 5 (RPI5)

The IMG file is also available for x86/x64