audio_player_device: Soundtrack Your Island

Overview

The audio_player_device lets you trigger, stop, and manage audio playback entirely from Verse code. You configure the actual sound asset (a sound wave or sound cue) in the UEFN Details panel, then drive when and for whom it plays through the API.

Reach for it when you need:

• Reactive music — start a combat track when a player enters a danger zone, stop it when they leave.
• Per-player audio — play a private success jingle only for the player who solved a puzzle (Heard by Instigator mode).
• Managed ambient loops — enable the device at round start, disable it (which also stops playback) at round end.
• Dynamic registration — add and remove players from the audio target list at runtime.

The device has two playback modes set in the Details panel:

• Heard by Everyone — Play() / Stop() affect all players.
• Heard by Instigator — Play(Agent) / Stop(Agent) target a single player; Register / Unregister manage the active target list.

API Reference

audio_player_device

Used to configure and play audio from the device location or from registered agents.

Full public surface, resolved verbatim from the live Epic digest (Fortnite.digest.verse).

audio_player_device<public> := class<concrete><final>(creative_device_base):

Methods (call these to make the device act):

Walkthrough

Scenario: A vault door puzzle. When a player steps on a pressure plate, a dramatic sting plays only for that player (Instigator mode). If they step off before the vault opens, the sting stops. When the vault is solved, a global fanfare plays for everyone and the sting device is disabled so it can't fire again.

# vault_audio_controller.verse
# Place this device in your scene alongside a trigger_device (pressure plate),
# two audio_player_devices, and a button_device (vault solve button).

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }
using { /Fortnite.com/Playspaces }

vault_audio_controller := class(creative_device):

    # The pressure plate trigger — player steps on it
    @editable
    PressurePlate : trigger_device = trigger_device{}

    # Audio player set to "Heard by Instigator" in Details panel
    # Assign a tense sting sound cue to this device
    @editable
    StingPlayer : audio_player_device = audio_player_device{}

    # Audio player set to "Heard by Everyone" in Details panel
    # Assign a victory fanfare sound cue to this device
    @editable
    FanfarePlayer : audio_player_device = audio_player_device{}

    # Button the player interacts with to "solve" the vault
    @editable
    VaultSolveButton : button_device = button_device{}

    # Track whether the vault has been solved so we ignore late triggers
    var VaultSolved : logic = false

    OnBegin<override>()<suspends> : void =
        # Subscribe to the pressure plate — fires with ?agent
        PressurePlate.TriggeredEvent.Subscribe(OnPlateTriggered)
        # Subscribe to the vault solve button
        VaultSolveButton.InteractedWithEvent.Subscribe(OnVaultSolved)

    # Called when a player steps on the pressure plate
    OnPlateTriggered(MaybeAgent : ?agent) : void =
        if (not VaultSolved?):
            if (A := MaybeAgent?):
                # Register this agent so the device tracks them,
                # then play the sting privately for them
                StingPlayer.Register(A)
                StingPlayer.Play(A)

    # Called when the player interacts with the vault solve button
    OnVaultSolved(Solver : agent) : void =
        if (not VaultSolved?):
            set VaultSolved = true

            # Stop the per-player sting for the solver
            StingPlayer.Stop(Solver)
            # Clear all registered agents — clean slate
            StingPlayer.UnregisterAll()
            # Disable the sting device entirely so it can't re-trigger
            StingPlayer.Disable()

            # Play the victory fanfare for everyone
            FanfarePlayer.Play()

Line-by-line breakdown:

Common patterns

Pattern 1 — Enable/Disable to gate audio across rounds

Disable the music device between rounds so stray triggers from linked devices can't fire it. Re-enable at round start.

# round_music_gate.verse
# Disable the audio player between rounds; enable it when a new round begins.
# Wire RoundStartTrigger and RoundEndTrigger to your round-management devices.

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }

round_music_gate := class(creative_device):

    # Audio player with looping background music assigned in Details
    @editable
    BattleMusic : audio_player_device = audio_player_device{}

    # Trigger fired by your round manager at round start
    @editable
    RoundStartTrigger : trigger_device = trigger_device{}

    # Trigger fired by your round manager at round end
    @editable
    RoundEndTrigger : trigger_device = trigger_device{}

    OnBegin<override>()<suspends> : void =
        # Start disabled — no music in the lobby phase
        BattleMusic.Disable()
        RoundStartTrigger.TriggeredEvent.Subscribe(OnRoundStart)
        RoundEndTrigger.TriggeredEvent.Subscribe(OnRoundEnd)

    OnRoundStart(MaybeAgent : ?agent) : void =
        # Enable the device so Play calls and linked triggers work
        BattleMusic.Enable()
        # Immediately start the music for everyone
        BattleMusic.Play()

    OnRoundEnd(MaybeAgent : ?agent) : void =
        # Disable stops current playback AND blocks future triggers
        BattleMusic.Disable()

Pattern 2 — Per-player registration for a team-specific soundtrack

Register only the members of a winning team so the victory music plays exclusively for them.

# team_victory_audio.verse
# After a team wins, register each winner and play a private victory track.
# Assumes you have a way to get the winning agents (here via a trigger per player).

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }
using { /Fortnite.com/Playspaces }

team_victory_audio := class(creative_device):

    # Audio player set to "Heard by Instigator" in Details panel
    @editable
    VictoryMusicPlayer : audio_player_device = audio_player_device{}

    # A trigger that fires once per winning player (e.g. from a Class Selector)
    @editable
    WinnerRegistrationTrigger : trigger_device = trigger_device{}

    # A trigger that fires once to actually start the music
    @editable
    PlayMusicTrigger : trigger_device = trigger_device{}

    # A trigger that fires to stop and clear everything (e.g. next round)
    @editable
    ClearMusicTrigger : trigger_device = trigger_device{}

    OnBegin<override>()<suspends> : void =
        WinnerRegistrationTrigger.TriggeredEvent.Subscribe(OnRegisterWinner)
        PlayMusicTrigger.TriggeredEvent.Subscribe(OnPlayVictoryMusic)
        ClearMusicTrigger.TriggeredEvent.Subscribe(OnClearMusic)

    # Register each winning agent as they are identified
    OnRegisterWinner(MaybeAgent : ?agent) : void =
        if (A := MaybeAgent?):
            VictoryMusicPlayer.Register(A)

    # Once all winners are registered, play for all of them at once
    OnPlayVictoryMusic(MaybeAgent : ?agent) : void =
        # Play() with no argument plays for ALL registered agents
        # when the device is in Heard by Instigator mode
        VictoryMusicPlayer.Play()

    # Clean up between rounds
    OnClearMusic(MaybeAgent : ?agent) : void =
        VictoryMusicPlayer.Stop()
        VictoryMusicPlayer.UnregisterAll()

Pattern 3 — Show/Hide the speaker prop dynamically

Reveal a visible speaker prop when a secret room unlocks, then hide it again when the room resets.

# secret_room_speaker.verse
# The audio_player_device's mesh is hidden until the secret room opens.
# A button reveals the speaker and starts music; a reset trigger hides it again.

using { /Fortnite.com/Devices }
using { /Verse.org/Simulation }

secret_room_speaker := class(creative_device):

    # The audio player whose speaker mesh we want to show/hide
    @editable
    SecretSpeaker : audio_player_device = audio_player_device{}

    # Button that unlocks the secret room
    @editable
    UnlockButton : button_device = button_device{}

    # Trigger that resets the room
    @editable
    ResetTrigger : trigger_device = trigger_device{}

    OnBegin<override>()<suspends> : void =
        # Hide the speaker mesh at game start
        SecretSpeaker.Hide()
        UnlockButton.InteractedWithEvent.Subscribe(OnRoomUnlocked)
        ResetTrigger.TriggeredEvent.Subscribe(OnRoomReset)

    OnRoomUnlocked(Unlocker : agent) : void =
        # Reveal the speaker prop and start the music
        SecretSpeaker.Show()
        SecretSpeaker.Play()

    OnRoomReset(MaybeAgent : ?agent) : void =
        SecretSpeaker.Stop()
        SecretSpeaker.Hide()

Gotchas

1. Play(Agent) and Stop(Agent) only work in Heard by Instigator mode

If your device is set to Heard by Everyone in the Details panel, calling Play(Agent) or Stop(Agent) will silently do nothing. Swap to the no-argument overloads Play() / Stop() for that mode.

2. Always unwrap ?agent before passing it to the API

The TriggeredEvent on a trigger_device sends ?agent (an optional). You must unwrap it with if (A := MaybeAgent?): before passing A to Register, Play(Agent), or Stop(Agent). Passing the raw optional is a compile error.

3. Disable() stops audio AND blocks future Play calls

Disable() is not a mute — it fully deactivates the device. Any subsequent call to Play() or Play(Agent) will do nothing until you call Enable() again. Use Stop() if you just want to pause playback while keeping the device active.

4. Register does not automatically start playback

Calling Register(Agent) only adds the agent to the target list. You still need to call Play() or Play(Agent) to actually start audio. Conversely, UnregisterAll() removes targets but does not stop currently playing audio — call Stop() first if needed.

5. Show() and Hide() are <transacts> — they can be rolled back

Show and Hide carry the <transacts> effect, meaning they participate in Verse's transaction system. If the enclosing expression fails, the visibility change is rolled back. Call them in a context where failure is handled, or outside a decision context if you want the change to always stick.

6. You cannot pass a raw string to SetInteractionText on companion devices

This doesn't apply to audio_player_device directly, but if you're combining it with a button_device that uses SetInteractionText, remember that the parameter is message, not string. Declare a localizes helper: MyLabel<localizes>(S:string):message = "{S}" and pass MyLabel("Unlock Music"). There is no StringToMessage function.