PowerToys Command Palette: Change Audio Device Extension

A native Windows PowerToys Command Palette extension that allows users to quickly view, select, and switch default audio input (microphones) and output (speakers, headphones) devices directly from the Command Palette interface.

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🚀 Features

• Quick Audio Switching: Change the default Windows input or output audio device with a single keystroke/click.
• Console, Multimedia & Communications Routing: Programmatically switches devices for all roles (Console, Multimedia, and Communications) to ensure apps like Discord, Teams, and games update correctly.
• Dynamic Device List: Queries active audio endpoints dynamically using low-level Windows Core Audio APIs (WASAPI).
• Active Device Highlighting: Displays the currently active/default device with an (Active) indicator.
• Multi-Architecture Support: Supports building and publishing for both x64 and ARM64 architectures.
• Zero-Dependency Asset Generator: Includes a helper script to scale and generate all required package icons and splash screens.
• Automated Bundle Packaging: Compilation and packaging script to produce single-file multi-architecture .msixbundle installers.

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🛠️ Technology Stack

• Target Framework: .NET 10.0 (with Target OS: net10.0-windows10.0.26100.0)
• UI Platform: PowerToys Command Palette Extension Toolkit (Microsoft.CommandPalette.Extensions)
• Interoperability: Windows Runtime (CsWinRT) and COM server activation (Shmuelie.WinRTServer)
• Low-Level APIs: Windows Multimedia Device APIs (WASAPI: IMMDeviceEnumerator, IMMDevice, IPolicyConfig)
• Package Format: Single-Project MSIX Package / MSIX Bundle

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📁 Repository Structure

ChangeAudioDeviceCommandPalleteExtension/
├── ChangeAudioDeviceCommandPalleteExtension.sln  # Visual Studio Solution file
├── Directory.Build.props                         # Shared build configurations (platforms, analyzers)
├── Directory.Packages.props                      # Centralized NuGet package version management
├── GenerateAssets.ps1                             # Script to generate asset resources (logos, splash screens)
├── buildForPublish.ps1                           # Build and bundle script for Release
└── ChangeAudioDeviceCommandPalleteExtension/
    ├── Assets/                                   # Application assets and tile icons
    ├── Pages/
    │   ├── AudioDeviceListPage.cs                # Command Palette list page showing input/output devices
    │   └── SetAudioDeviceCommand.cs              # Action executed when selecting a device
    ├── AudioManager.cs                           # Interop layer querying WASAPI COM interfaces
    ├── CoreAudioInterop.cs                       # COM definition interface declarations (IMMDevice, ERole, etc.)
    ├── ChangeAudioDeviceCommandPalleteExtension.cs # COM extension entry point implementing IExtension
    ├── ChangeAudioDeviceCommandPalleteExtensionCommandsProvider.cs # Registers commands to Command Palette
    ├── Package.appxmanifest                      # AppX package registration manifest (COM server & AppExtension)
    ├── Program.cs                                # Main entry point starting WinRTServer
    └── app.manifest                              # Application identity manifest

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💻 How It Works

1. AppExtension Integration: The extension registers as a com.microsoft.commandpalette app extension in Package.appxmanifest. PowerToys Command Palette automatically discovers it.
2. COM Server Activation: When the user opens the Command Palette, the host launches ChangeAudioDeviceCommandPalleteExtension.exe with arguments -RegisterProcessAsComServer and instantiates the COM class via its Guid (e82d5dfa-d102-421a-a77b-12cdfb71b64c).
3. Core Audio Query: Using IMMDeviceEnumerator, the helper class AudioManager enumerates active render (speakers) and capture (microphones) endpoints.
4. Device Selection: When selected, the private IPolicyConfig.SetDefaultEndpoint COM interface is invoked to register the selected device ID as the system default.
5. UI Refresh: The list page is refreshed to update the (Active) indicator and a confirmation toast is displayed.

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⚙️ Development & Build Instructions

Prerequisites

• Windows 10 or 11
• .NET 10 SDK
• Windows SDK (needed for makeappx.exe to build the MSIX bundle)

Build for Debugging

Open the solution file ChangeAudioDeviceCommandPalleteExtension.sln in Visual Studio 2022 or build using CLI:

dotnet build

Packaging for Release

Run the automated build and publish script. This script builds both x64 and ARM64 packages in Release mode and compiles them into a single, publishable .msixbundle package:

.\buildForPublish.ps1

The output bundle will be located at: ChangeAudioDeviceCommandPalleteExtension/ChangeAudioDeviceCommandPalleteExtension_1.0.0.0_Bundle.msixbundle

Asset Generation

If you want to customize the extension's icon, place your master image at a target path and update/run GenerateAssets.ps1:

.\GenerateAssets.ps1

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📜 License

This project is licensed under the MIT License - see the LICENSE file for details.