advanced-camera-card/docs/usage/2-way-audio.md

2-way Audio

This card supports 2-way audio (e.g. transmitting audio from a microphone to a suitably equipped camera). In general, due to the myriad of different cameras, security requirements and browser limitations getting 2-way to work may be challenging.

Requirements

Environmental requirements

• Must have a camera that supports audio out (otherwise what's the point!)
• Camera must be supported by go2rtc for 2-way audio (see supported cameras).
• Must be accessing your Home Assistant instance over https. The browser will enforce this.

Card requirements

• Only Frigate cameras are supported.
• Only the go2rtc and go2rtc-experimental live providers are supported.
• The browser must be able to reach go2rtc over WebRTC. Outbound audio always travels on its own WebRTC connection, regardless of what mode is carrying the video.

If your setup supports 2-way audio but detection is intermittent on load:

• Increase cameras[].go2rtc.metadata_fetch_timeout_seconds.
• Or force the capability with cameras[].capabilities.force: ['2-way-audio'].

If detection never succeeds for a camera, the go2rtc stream itself may not offer 2-way audio -- see go2rtc live provider configuration.

Example configuration

type: custom:advanced-camera-card
cameras:
  - camera_entity: camera.office
    live_provider: go2rtc
    go2rtc:
      modes:
        - webrtc
      # Optional: For slower cameras increase timeout (default: 2)
      metadata_fetch_timeout_seconds: 10

Usage

Two-way audio is driven by the call menu button (a phone icon). It is enabled by default and appears in the live view whenever the selected camera -- or one of its dependencies -- supports 2-way audio.

• Tap the call button to start an outbound call. An on-screen overlay appears with controls to mute/unmute the microphone, mute/unmute the inbound audio, and end the call. When more than one 2-way-audio camera is available the button becomes a submenu with one entry per camera.
• Inbound calls (started by a view.triggers.actions.trigger: call trigger -- e.g. a doorbell) open the overlay in a ringing state with only two buttons: a red Reject and a green Answer.
• The call menu button itself tracks the call state: tap it to start or answer a call and to hang up an active one, and while an inbound call is ringing hold it to reject. This lets you drive the whole call from the menu when the standard call controls are hidden with live.controls.call.enabled: false -- see Driving calls from the menu.
• When a call is answered (outbound calls are answered by definition) the inbound audio is unmuted automatically, so the caller can be heard. The microphone stays muted by default (push-to-talk) -- tap the microphone button in the overlay to speak. Both behaviors are configurable via live.microphone.auto_unmute and live.auto_unmute.
• The camera loads without the microphone connected, unless the always_connected microphone option is set to true. Starting a call opens a separate connection that carries your voice to the camera; ending the call closes it. The camera's audio input is therefore occupied only while a call is in progress, leaving it free for other applications the rest of the time. Expect under half a second between starting a call and being audible on a local network, and a little more remotely. The video keeps playing throughout.
• The browser asks for microphone permission when a call needs it. How often it asks depends on the browser: Chrome remembers the choice for the site, Safari asks once per page load, and Firefox asks for every call unless Remember this decision is ticked. Set always_connected to true to be asked once at card load instead.
• While a call is in progress the card locks disruptive actions (camera and substream changes, casting, reload, etc.) so an accidental tap, swipe, or button press doesn't cut the call off. Set live.controls.call.lock to false to disable this.
• End the call with the overlay's end-call button. When the call ends the microphone and inbound audio are muted again, and the microphone is disconnected. The exception is always_connected, which holds the microphone connected for as long as the card is running.

Calls can also be controlled programmatically with the call_start, call_answer, and call_end actions -- for example, from an automation that fires when a doorbell sensor triggers. The call condition can be used to show or hide elements while a call is in progress.

Call lifecycle

The diagram below traces a call from start to finish:

Talking with a single tap

By default, two taps are needed to speak: start (or answer) the call so you can hear, then unmute the microphone via the in-call overlay so you can be heard. This push-to-talk default keeps the microphone muted until you explicitly choose to speak.

To collapse that to a single tap, unmute the microphone automatically when a call is answered:

live:
  microphone:
    auto_unmute: ['call']

For outbound calls the microphone opens the moment the call starts; for inbound calls it opens the moment you press the green answer button. Leave auto_unmute empty (the default) to always start muted regardless.