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Ambrogio

Choose audio devices

The satellite listens with one microphone and answers through one speaker (How voice works). Without AMBROGIO_MICROPHONE and AMBROGIO_SPEAKER, the satellite uses the system’s default microphone and speaker. When the device has more than one, name the one you want.

1. List the devices

Section titled “1. List the devices”

On the satellite’s device, run the satellite image with a command that lists the devices, using the release of your compose.yaml:

Terminal window
docker run --rm --device /dev/snd --entrypoint node ghcr.io/ambrogio-app/ambrogio-satellite:v0.9.0 \
  -e "import('decibri').then(d => { console.table(d.Microphone.devices()); console.table(d.Speaker.devices()); })"

The first table shows microphones, the second speakers. Note the name and id columns. ALSA may print some warnings first; you can ignore them.

2. Pick a selector

Section titled “2. Pick a selector”

Each of AMBROGIO_MICROPHONE and AMBROGIO_SPEAKER takes a string, which works in one of two ways:

  • A stable ID that starts with alsa:, copied from the id column, such as alsa:plughw:CARD=Device,DEV=0. This is the most precise choice.
  • Part of the name, such as "USB" or "ReSpeaker". Case does not matter. Use text that only one device’s name contains; when several names match, use the ID instead.

A number is treated as text, not as the row index.

Add the selectors to the environment section of the satellite’s compose.yaml:

AMBROGIO_MICROPHONE: USB
AMBROGIO_SPEAKER: alsa:plughw:CARD=Headphones,DEV=0

You can set only one of the two; the other stays on the default.

3. Restart and test

Section titled “3. Restart and test”

Recreate the satellite with docker compose up -d. A selector that matches no device is never replaced by the default, so a mistake shows up instead of going unnoticed:

  • A wrong microphone stops the satellite at startup, with "event":"satellite_startup_failed" and the message Microphone could not be started in the log.
  • A wrong speaker is found only when the satellite first plays something. After the wake word you hear no beep, and the log shows "event":"satellite_ready_cue_failed".

Say the wake word once after every change to check both.

Device IDs can differ between machines. List them again after moving the satellite.