So, we are now at London, next to a MI6 laptop with the elliptic curve firewall...and starting today

Basic Virtual PCM Devices for Playback/Capture, ALSA

ALSA arranges sound cards and their components into a heirarchy of cards, devices and subdevices. It reflects the structure and capabilities of the hardware as seen by ALSA. A card can be denoted by a stringID or a zero-based index. Devices of each card are also enumerated from 0. Different devices can be opened and used independently of each other. Typically, specifying a card and device will suffice for handling audio streams. Finally, some devices may have a separate subdevice for each channel. Like devices, subdevices are identified by a zero-based index.

http://nairobi-embedded.org/alsa_pcm_plugins_capture.html