Quick fix: Right-click speaker icon → Sounds → Recording tab → double-click your mic → Levels tab. If Microphone Boost slider is greyed out, the audio driver doesn’t expose the boost. Install the manufacturer’s audio driver (Realtek, Conexant) instead of Microsoft’s generic. For USB mics: open the mic’s vendor app for hardware-level gain control.

Your microphone is too quiet on calls. You open Levels expecting to crank Microphone Boost — the slider is greyed out. Cause: Microsoft’s generic USB Audio Class driver doesn’t expose the boost control; only vendor drivers do.

Symptom: Microphone Boost slider is greyed out in Levels tab; can’t increase mic input level beyond 100%.
Affects: Windows 11 (and Windows 10) with generic USB audio drivers.
Fix time: ~15 minutes.

What causes this

Windows’s Microphone Boost is a software amplifier that multiplies the input signal — useful when the mic outputs low levels even at 100%. The boost requires driver support: vendor-specific Realtek HD Audio, Conexant SmartAudio, Intel Smart Sound, and some USB mic drivers include it. Microsoft’s generic USB Audio Class driver doesn’t.

If you installed a vendor driver then later updated and Windows replaced it with the generic, Boost disappears.

Method 1: Install the manufacturer’s audio driver

The standard fix.

Identify your audio chipset: Device Manager → Sound, video and game controllers. Right-click your device → Properties → Details tab → Hardware Ids. First entry shows VEN_xxxx&DEV_xxxx. Common vendors:
- 10EC = Realtek
- 14F1 = Conexant
- 8086 = Intel
For laptop: visit the laptop manufacturer’s support site (Dell, HP, Lenovo). Download the latest audio driver for your model and Windows 11 64-bit.
For desktop: visit the motherboard manufacturer’s support site. Download Realtek/manufacturer audio driver.
Run the installer. Reboot.
Open Sound → Recording → double-click mic → Levels tab. Microphone Boost slider should now be available (typically 0–30 dB range).
Set boost: 10–20 dB is reasonable for soft speakers. Too high causes clipping.
Test with Voice Recorder app.

This restores Boost on laptops and desktops with vendor drivers.

Method 2: Configure USB microphone’s hardware gain

For USB microphones (Blue Yeti, HyperX, Audio-Technica USB).

Most USB mics have a physical gain knob on the mic itself or its base. Adjust upward.
For software-level gain: check the manufacturer’s app:
- Blue Yeti: Blue Sherpa app from Microsoft Store.
- HyperX: HyperX NGENUITY from Microsoft Store.
- Audio-Technica USB mics: usually no app; hardware gain only.
- Elgato Wave: Wave Link app.
For ASIO-compatible USB mics: install vendor’s ASIO driver. Adjust gain in the vendor’s control panel.
For Windows Sound Levels: the slider is hardware gain pass-through; if Boost is greyed, hardware doesn’t support software boost.
For phantom-powered XLR mics (Blue Spark, RØDE NT1): use an audio interface (Focusrite Scarlett, Audient iD4) which has its own gain knob and ASIO driver.

USB mic boost is usually at the hardware level.

Method 3: Add software-level gain via third-party tools

For when neither Windows’ Boost nor hardware gain is sufficient.

Install Voicemeeter from vb-audio.com (free, donationware). It’s a virtual audio mixer with software gain.
Configure Voicemeeter: set your mic as Hardware Input 1, route to VoiceMeeter Output as the new system mic.
In apps (Zoom, Teams, OBS): set microphone to VoiceMeeter Output instead of the physical mic.
Voicemeeter’s Gain slider provides up to +24 dB of software boost.
For one-app boost (e.g., Discord): Discord settings → Voice & Video → Input volume slider can go to +200% as a software boost.
For OBS streaming: use the Gain filter on the mic source. Adjust 0–30 dB.
Caution: software boost amplifies noise as much as signal. Reduce ambient noise first (move closer to mic, use directional mic) before adding boost.

This is the right path when hardware can’t deliver enough gain.

How to verify the fix worked

Recording tab → double-click mic → Levels tab. Microphone Boost slider is no longer greyed out.
Speak at normal volume. Recording level meter (Sound → Recording → right pane) reaches 50–80%.
Voice Recorder app: speak. Playback is audible at normal volume without straining to hear.

If none of these work

If you can’t enable Boost after installing vendor drivers, the mic itself has hardware-low output. Test with another mic: borrow a different mic temporarily. If the alternate mic has normal volume, the original mic is faulty or low-sensitivity. Check mic position: speaking from 6 inches away gives much louder signal than 24 inches. Move the mic closer. For laptops with poor built-in mic: built-in mics are typically optimized for noise suppression, not loudness. They sound “quiet but clear” intentionally. External mic gives much better signal-to-noise. For headset mics with thin boom: the small mic capsule has limited output. Use a desktop USB mic or table mic for louder pickup. For headsets via 3.5mm jack: TRRS jacks combine mic and headphones. Some PCs have only TRS (no mic) front jacks. Use a splitter cable or USB headset.

Bottom line: Microphone Boost requires vendor driver. Install Realtek/Conexant audio driver from your laptop/motherboard manufacturer. For USB mics, use vendor app or hardware gain.