MicGuard

Keeps your default mic and its volume exactly where you set them.

Windows (and games like Black Ops 3) love to silently change your default microphone and its recording volume. MicGuard sits in your tray and snaps both back the instant anything touches them — measured restore time ~50 ms.

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Install

1. Download MicGuard.exe from the latest release.
2. Put it somewhere permanent (e.g. Documents\MicGuard\) and double-click it.
3. Done. First launch auto-selects the mic that's currently your default + default-communications device and opens Settings so you can pick the volume to hold and whether to start with Windows.

Note

Windows SmartScreen may warn because the exe is unsigned — click More info → Run anyway. Needs the WebView2 runtime for the settings window (already on every Windows 11 PC and any PC with Edge).

What it does

• 🎯 Holds your default mic AND your default output — if anything changes the default device (any role: Default Device and Default Communications Device), it's changed back immediately, for both capture and render.
• 🔁 Priority fallback lists — rank multiple mics/outputs; if your top pick disconnects, MicGuard falls back to the next one in line and switches straight back the instant your top pick reconnects. No more "Windows picked some random mic and forgot to switch back." Survives USB re-plugs that quietly change Windows' internal device IDs — devices are re-adopted by name automatically.
• 🗂️ Named profiles — bundle a mic list + output list under a name (e.g. "Gaming", "Streaming") and switch between them from the tray menu.
• 🔊 Holds your mic volume — BO3, Discord, Windows Update, anything moves the level → restored in ~50 ms. Unmutes too. Output volume can be held the same way per-device, or left alone so your volume keys keep working.
• 🔔 Fallback alerts — a small, no-focus-stealing popup tells you when a device drops out and again when it's back, without interrupting whatever you're doing (games included).
• ⌨️ Volume hotkeys with an on-screen display (off by default) — global shortcuts for system, per-app, or the active window's volume (e.g. bump Discord without alt-tabbing), with a game-safe OSD that never steals focus.
• 🎚️ Mixer popup with boost-past-100% — a dedicated hotkey (default Shift+F3 on fresh installs) pops a small gkey-style mixer over your game; digits, arrows, or WASD (nav mode is a setting) pick a row and nudge it, it scrolls through every app currently playing audio, bars pulse with live levels, M mutes the selected row, and boosting an app past 100% ducks the game (or everything else) to make room, all without alt-tabbing.
• 🖥️ Fullscreen-game friendly — popups appear on your game's own monitor when Windows allows it; if a specific game insists on minimizing instead, MicGuard notices once, restores your game instantly, remembers that game, and moves its popups to a game-free monitor from then on.
• 🎙️ Mic EQ (optional extension) — one guided setup unlocks real gain boost (past your driver's max) and bass boost on your mic, saved per profile, applied instantly. Powered by Equalizer APO.
• ⚡ Event-driven, ~0% CPU — no polling loops. It subscribes to Windows Core Audio change events and sleeps otherwise.
• 🖱️ Left-click the tray icon → Settings. Right-click → full menu (pause enforcement, switch profiles, re-apply now, check for updates, uninstall, quit).
• 🚀 Start with Windows via a per-user registry Run entry — no Task Scheduler, no services, no admin rights.
• 🔔 Updates ask first, never act silently — it checks GitHub Releases on launch; you decide. If an in-place update fails it opens this releases page so you can grab the exe manually.
• 🧹 Clean uninstall from the tray — removes the startup entry, its settings folder, and the exe itself. Zero leftovers.

Footprint

Path	Purpose
%APPDATA%\MicGuard\config.json	settings
%APPDATA%\MicGuard\micguard.log	small log
HKCU\...\CurrentVersion\Run\MicGuard	startup entry (only if enabled)

That's everything. No installer, no services, no telemetry.

Building from source

git clone https://github.com/Bristopher/MicGuard
cd MicGuard
uv sync
uv run pythonw micguard.py     # run it
.\release.ps1                  # maintainers: bump + build + tag + publish

Full guide: Docs/Development/Build-and-Release.md

How it works

One Python file. pycaw/comtypes register Core Audio callbacks (IAudioEndpointVolumeCallback for volume, IMMNotificationClient for device changes); any event wakes a single enforcement thread that re-asserts the configured device (via the same IPolicyConfig COM interface SoundSwitch/EarTrumpet use) and volume. A slow 15-second watchdog backstops missed events — that's the only "polling", and it's one COM call. The UI is real HTML/CSS rendered by Windows' built-in WebView2 (frameless pywebview windows — pixel-level styling without shipping Electron); the whole thing compiles to a single exe with PyInstaller.

Architecture deep-dive: Docs/Architecture.md