Windows Native Toolkit | Audio System Library

Windows audio-device enumeration, default-device, volume, mute, peak, format, and enable-state nodes.

Use this library to inspect and control Windows audio endpoints for playback and recording.

Python examples use Unreal's reflected API names through the unreal module. Getter functions with output pins are shown using the tuple return style exposed by Unreal Python.

Pure Getters

Getter nodes such as Get Default Audio Device, Get Audio Volume, Is Audio Muted, and Get Audio Peak are now pure Blueprint functions. Public error-message pins were removed; failures are logged and the node returns false when applicable.

Get Audio Devices

Returns all active audio devices for the selected input or output flow.

Pin	Direction	Purpose
`Flow`	Input	Choose `Output` or `Input`.
`Return Value`	Output	`TArray<FAudioDeviceInfo>` for active endpoints.

FAudioDeviceInfo fields:

bIsDefaultDevice
bIsCommunicationDevice
DeviceName
DeviceID

C++ Example

#include "AudioSystemLibrary.h"

const TArray<FAudioDeviceInfo> Devices = UAudioSystemLibrary::GetAudioDevices(EWNTAudioDeviceFlow::Output);

Python Example

import unreal

devices = unreal.AudioSystemLibrary.get_audio_devices(unreal.WNTAudioDeviceFlow.OUTPUT)

Get Default Audio Device

Returns the default Windows endpoint for the selected flow and role.

Pin	Direction	Purpose
`Flow`	Input	Choose `Output` or `Input`.
`Role`	Input	Choose `System Default` or `Communication Default`.
`Return Value`	Output	True when the default device was found.
`OutDevice`	Output	`FAudioDeviceInfo` for the selected default device.

C++ Example

#include "AudioSystemLibrary.h"

FAudioDeviceInfo DefaultDevice;
const bool bFound =
    UAudioSystemLibrary::GetDefaultAudioDevice(
        EWNTAudioDeviceFlow::Output,
        EWNTAudioDeviceRole::System,
        DefaultDevice);

Python Example

import unreal

found, default_device = unreal.AudioSystemLibrary.get_default_audio_device(
    unreal.WNTAudioDeviceFlow.OUTPUT,
    unreal.WNTAudioDeviceRole.SYSTEM,
)

Set Default Audio Device

Sets the normal Windows default audio device.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Return Value`	Output	True when the device was set successfully.

C++ Example

#include "AudioSystemLibrary.h"

const bool bChanged = UAudioSystemLibrary::SetDefaultAudioDevice(DeviceID);

Python Example

import unreal

changed = unreal.AudioSystemLibrary.set_default_audio_device(device_id)

Set Communication Audio Device

Sets the Windows communications default audio device.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Return Value`	Output	True when the communications device was set successfully.

C++ Example

#include "AudioSystemLibrary.h"

const bool bChanged = UAudioSystemLibrary::SetCommunicationAudioDevice(DeviceID);

Python Example

import unreal

changed = unreal.AudioSystemLibrary.set_communication_audio_device(device_id)

Set Audio Volume

Sets endpoint volume from 0.0 to 1.0.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Volume`	Input	Volume value from `0.0` to `1.0`.
`Return Value`	Output	True when the volume was updated.

C++ Example

#include "AudioSystemLibrary.h"

const bool bChanged = UAudioSystemLibrary::SetAudioDeviceVolume(DeviceID, 0.5f);

Python Example

import unreal

changed = unreal.AudioSystemLibrary.set_audio_device_volume(device_id, 0.5)

Get Audio Volume

Reads endpoint volume from 0.0 to 1.0.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Return Value`	Output	True when the volume was read successfully.
`OutVolume`	Output	Current volume from `0.0` to `1.0`.

C++ Example

#include "AudioSystemLibrary.h"

float Volume = 0.0f;
const bool bRead = UAudioSystemLibrary::GetAudioDeviceVolume(DeviceID, Volume);

Python Example

import unreal

read, volume = unreal.AudioSystemLibrary.get_audio_device_volume(device_id)

Set Audio Muted

Sets endpoint mute state.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`bMuted`	Input	Desired mute state.
`Return Value`	Output	True when mute state was updated.

C++ Example

#include "AudioSystemLibrary.h"

const bool bChanged = UAudioSystemLibrary::SetAudioDeviceMuted(DeviceID, true);

Python Example

import unreal

changed = unreal.AudioSystemLibrary.set_audio_device_muted(device_id, True)

Is Audio Muted

Reads endpoint mute state.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Return Value`	Output	True when mute state was read successfully.
`bMuted`	Output	Current mute state.

C++ Example

#include "AudioSystemLibrary.h"

bool bMuted = false;
const bool bRead = UAudioSystemLibrary::GetAudioDeviceMuted(DeviceID, bMuted);

Python Example

import unreal

read, muted = unreal.AudioSystemLibrary.get_audio_device_muted(device_id)

Get Audio Peak

Reads the live endpoint peak level from 0.0 to 1.0.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Return Value`	Output	True when the peak value was read successfully.
`OutPeakValue`	Output	Live peak value from `0.0` to `1.0`.

C++ Example

#include "AudioSystemLibrary.h"

float PeakValue = 0.0f;
const bool bRead = UAudioSystemLibrary::GetAudioDevicePeak(DeviceID, PeakValue);

Python Example

import unreal

read, peak_value = unreal.AudioSystemLibrary.get_audio_device_peak(device_id)

Get Supported Audio Device Default Formats

Returns the shared-mode formats that Windows currently accepts for a device.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`Return Value`	Output	`TArray<FWNTAudioDeviceFormat>` accepted by the device.

FWNTAudioDeviceFormat fields:

FormatIndex
ChannelCount
SampleRate
BitsPerSample
Description

C++ Example

#include "AudioSystemLibrary.h"

const TArray<FWNTAudioDeviceFormat> Formats =
    UAudioSystemLibrary::GetSupportedAudioDeviceFormats(DeviceID);

Python Example

import unreal

formats = unreal.AudioSystemLibrary.get_supported_audio_device_formats(device_id)

Set Audio Device Default Format

Sets the shared-mode default format by using the FormatIndex returned by Get Supported Audio Device Default Formats.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`FormatIndex`	Input	Format index returned by `Get Supported Audio Device Default Formats`.
`Return Value`	Output	True when the format was updated successfully.

C++ Example

#include "AudioSystemLibrary.h"

const bool bChanged = UAudioSystemLibrary::SetAudioDeviceDefaultFormat(DeviceID, FormatIndex);

Python Example

import unreal

changed = unreal.AudioSystemLibrary.set_audio_device_default_format(device_id, format_index)

Set Audio Device Enabled

Enables or disables an audio endpoint.

Pin	Direction	Purpose
`DeviceID`	Input	Device ID returned by `Get Audio Devices`.
`bEnabled`	Input	Desired enabled state.
`Return Value`	Output	True when the device state was updated successfully.

C++ Example

#include "AudioSystemLibrary.h"

const bool bChanged = UAudioSystemLibrary::SetAudioDeviceEnabled(DeviceID, false);

Python Example

import unreal

changed = unreal.AudioSystemLibrary.set_audio_device_enabled(device_id, False)

Audio System Library

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