cat /proc/asound/cards
 0 [PCH            ]: HDA-Intel - HDA Intel PCH
                      HDA Intel PCH at 0xc8710000 irq 28
 1 [Loopback       ]: Loopback - Loopback
                      Loopback 1
 2 [Plus           ]: USB-Audio - M-Track Plus
                      M-Audio M-Track Plus at usb-0000:00:14.0-2, high speed