Volume Mixer Plugin for Macro Deck 3

A Macro Deck 3 plugin that provides Windows audio control directly from your macro pad. Monitor and control audio devices, per-application volumes, and default device selection, a lightweight alternative to Voicemeeter Banana for basic audio routing needs.

This is the Macro Deck 3 port of MacroDeckVolumeMixerPlugin (Macro Deck 2). The behaviour is the same; the plugin model is not. See What changed from Macro Deck 2.

Windows only (Windows Core Audio API). win-x64, framework-dependent on .NET 10.

Features

Current

Default Audio Device Info: See which playback device is currently set as default (Multimedia and Communications roles) Default Microphone Info: See which input device is currently set as default Per-Application Volume Control: View and adjust volume for individual apps (Spotify, Discord, games, etc.) Volume Sliders: Bind a slider widget straight to an application's volume, in both orientations Mute/Unmute Apps: Toggle mute state for specific applications Switch Default Output: Change the default playback device with a button press Switch Default Microphone: Change the default input device with a button press Switch Output + Microphone: Change both output and input devices together (profile switching) Device Switching: Switch output and/or microphone devices via actions Toggle Mode: Toggle between 2 devices with a single button press (output, microphone, or both)

Requirements

Macro Deck 3 (>=3.0.0-0) Windows 10/11 (uses Windows Core Audio API) .NET 10 Runtime (shipped with Macro Deck)

Installation

From the plugin artifact

Download the .macroDeckPlugin artifact from the releases. Import it in Macro Deck on your PC.

Manual build

git clone https://github.com/DiegoFdezAb/MacroDeck3VolumeMixerPlugin cd MacroDeck3VolumeMixerPlugin

Build, test, pack dotnet build dotnet test macrodeck-plugin build --source src/VolumeMixerPlugin --output ./artifacts macrodeck-plugin validate --artifact ./artifacts/com.diegofdezab.volume-mixer-.macroDeckPlugin

An installed plugin lives under %appdata%\MacroDeck\plugins\com.diegofdezab.volume-mixer\versions\\, with a manifest.json, a current.json pointing at the active version, and one runtimes\\ directory per declared platform. Do not copy a loose DLL into that folder: the host verifies the files[] digests in the manifest.

Usage

Variables (exposed to Macro Deck)

Variable Name Type Description volumemixerdefaultdevice String Name of the current default multimedia output device volumemixercommdevice String Name of the current default communications output device volumemixerdefaultmic String Name of the current default multimedia input device volumemixercommmic String Name of the current default communications input device volumemixerappvolume Numeric Volume level (0-100) for a tracked app, writable volumemixerappmuted Boolean Mute state for a tracked app, read only

The four device variables are polled every 2 seconds. Example button label: {volumemixerdefaultdevice}.

Per-application variables come from the variable catalog: pick an app that is producing audio and bind volumemixerappvolume or volumemixerappmuted. The part is the process name lowercased, with every run of characters outside a-z0-9 replaced by , and a leading non-letter prefixed with app. Example: Spotify: {volumemixerappspotifyvolume}%.

Sliders

volumemixerappvolume is declared writable, so a slider widget binds to it directly and writes the application volume as you drag. The value is clamped to 0-100 before it reaches the audio session. Both slider orientations work; Macro Deck sends the adjustment, not a press, so the plugin never sees a button.

volumemixerappmuted stays read only. Use the toggle-mute action for it.

Actions

Action Id Configuration Set Default Output set-default-output Device name or ID. Toggle mode: select 2 devices to switch between them Set Default Microphone set-default-mic Device name or ID. Toggle mode: select 2 microphones to switch between them Set Default Output + Microphone set-default-pair Output device, Input device. Each can optionally use toggle mode Set App Volume set-app-volume App name, Volume (0-100) Volume Up/Down volume-up / volume-down App name. Adjusts by 5% Mute App toggle-mute App name Refresh Devices refresh-devices None

Device pickers are dynamic: they list the currently active endpoints. A device unplugged between configuration and press fails the action truthfully instead of switching blindly.

Toggle Mode

All device switching actions support a Toggle Mode that switches between 2 devices with a single button press:

Select Device 1 and Device 2 in the action configuration Each press switches to the device that is not currently default The plugin detects the current device itself

Note: The two devices must be different. If a device becomes unavailable (disconnected), the toggle will not execute and a warning is logged.

Example button configurations

Show current default device:

Label: {volumemixerdefaultdevice} No action needed, the variable updates automatically

Spotify volume:

Label: Spotify: {volumemixerappspotifyvolume}% Slider bound to volumemixerappspotifyvolume Long press action: Volume Down (App: Spotify)

What changed from Macro Deck 2

The behaviour of every action and variable is preserved. The packaging and the contract are not.

Macro Deck 2 Macro Deck 3 Plugin model In-process extension Out-of-process plugin, its own .NET process Artifact Loose DLL copied to %appdata%\Macro Deck\plugins\ .macroDeckPlugin package with a signed manifest Manifest ExtensionManifest.json manifest.json, schema validated, digests recomputed on pack Runtime .NET 8 .NET 10, shipped with the host Entry point net8.0-windows DLL runtimes/win-x64/, framework-dependent Identity Extension id com.diegofdezab.volume-mixer, publisher DiegoFdezAb Strings Inline literals Localization/Strings.resx, English shipped, more languages fall back to it Install Manual copy or MD2 Extension Store Artifact import, MD3 Store submission Verification Manual macrodeck-plugin test, conformance report required before publishing

Two things are new rather than ported:

Writable volume variables, so a slider can drive an application's volume Dynamic device pickers resolved from the live endpoint list at configuration time

Screenshot

Screenshot What it shows docs/screenshots/set-default-output-toggle.png An action button whose label is the {volumemixerdefaultdevice} variable, running the set-default-output action in toggle mode between two devices

Technical details

Audio API

This plugin uses NAudio with the Windows Core Audio API (WASAPI) to:

Enumerate audio endpoints (MMDeviceEnumerator) Access audio sessions per device (AudioSessionManager) Control per-application volume (SimpleAudioVolume)

Memory management

The plugin disposes its COM objects so it does not leak audio sessions:

Single MMDeviceEnumerator instance, disposed on shutdown Device cache with a 15 second lifetime Sessions released after each snapshot

Limitations

Windows only: Core Audio API is not available on Linux or macOS No audio routing: cannot route audio between devices like Voicemeeter Process-based detection: apps are identified by process name, not window title

Troubleshooting

Plugin not loading

Check Macro Deck is >=3.0.0-0 Check the plugin folder holds a version directory with a manifest.json Read the logs at %appdata%\MacroDeck\logs\

Apps not showing

The app must be actively producing audio to appear Some system sounds show as empty or unnamed sessions Store apps may show under a different process name

Volume changes not applying

Ensure the app is not locked by another volume controller Some apps ignore external volume changes (rare)

A slider moves but the volume does not

The variable must be the volume one, the muted one is read only The app must have an audio session at that moment, otherwise the write reports unavailable

Contributing

Contributions welcome. Please:

Fork the repository Create a feature branch Submit a pull request

For bugs or feature requests, open an issue.

License

MIT License. See LICENSE for details.

Credits

NAudio: audio library for .NET Macro Deck: the macro pad software MacroDeckVolumeMixerPlugin: the Macro Deck 2 original this is ported from Inspired by the need for simple audio control without Voicemeeter overhead