Audio and display glasses route all sound through shared speakers, managed by Android's audio focus system. When an app starts playback, it requests audio focus. Concurrent streams seamlessly duck, pause, or stop in the background without playing audio cues or announcing state changes. Understand physical input routing for audio glasses.
Choose the behavior that fits your content
The right behavior depends on what the user would lose if they missed part of your audio. If a few seconds of music sit under a notification, nothing important is lost. If a sentence of an audiobook gets talked over, the user loses the story.
- Music and ambient audio will duck and keep playing because there's no missed information.
- Spoken content, like audiobooks, will pause and rewind the audio, so the user doesn't miss information.
- Calls, live translation, and agent readouts need a user's full attention, so other audio interruptions are paused.
- Short, important updates, like a navigation update, will duck briefly to the incoming sound.
The system assigns behavior based on the content type assigned. Learn more about optimizing audio focus.
Playing earcons alongside other audio
How an earcon plays over other audio depends on its job. Earcons that confirm the user's own action are instant and frequent, so they mix on top of whatever is playing. All other earcons carry information the user needs to hear, so they duck other audio briefly and then let it return.
Designing for each behavior
If your earcon mixes, design it to cut through on its own with a clean, defined attack, a tight duration and a distinct timbre. Nothing gets out of its way, so its character has to do the work.
If your earcon ducks, design it to account for the ducking curve. The other audio takes a moment to dip, so a clear start helps the earcon register before the dip finishes.
System Overrides
Certain system events—like privacy indicators, calls, and critical hardware alerts—always override other audio and app focus. They also have a set of earcon and LED behaviors.
