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Platform: Reality Apps (mobile)

Using a USB External Mic

Last updated: July 18, 2026 at 09:41

Verifier Guide: USB External Mic (Current App)

Applies to: VRA Standard as it ships today
Important: The app does not specially select or lock an external mic. Android may route a USB-C mic into recording when it recognizes it. Acoustic room checks (chirps) are designed for the phone speaker + phone mic.

What works / what doesn’t

Goal With USB mic plugged in

Interview / speech audio

Often works (verify with meter tap-test)

Acoustic room chirps

Often unreliable — treat as not trustworthy

GPS, sensors, seals, hashes - Unaffected

Required session flow

1. Open the session (phone only)

  1. Do not plug in the USB receiver yet.

  2. Record a short proof video with the phone’s built-in mic.

  3. Wait until that clip finishes and saves.

This is your opening acoustic bookend.

2. Connect the USB mic for interviews

  1. Plug in the USB-C receiver / mic.

  2. Wait a few seconds for Android to detect it.

  3. Switch to video or audio mode.

  4. Do the tap-test before any interview:

    • Speak into (or scratch) the lav / mic.

    • Watch the in-app audio meters.

    • Meters should move clearly when you talk into the external mic.

  5. If meters don’t move:

    • Unplug and re-plug.

    • Try again.

    • If still dead, do not use that mic on this phone — record with the phone mic only.

3. Record street interviews

  • Keep the USB mic plugged in for interview clips.

  • Use the meters as your “audio is live” check.

  • Expect good speech audio when the tap-test passed.

  • Do not rely on acoustic / room-check results for these clips.

4. Close the session (phone only)

  1. Unplug the USB receiver.

  2. Record a short final proof video with the phone only.

  3. Then seal / finish the session.

This is your closing acoustic bookend. Prefer a short video, not only photos.

Quick rules

  1. First clip: phone only (no USB).

  2. Interviews: USB OK after a successful meter tap-test.

  3. Last clip before seal: phone only (USB unplugged).

  4. Never seal immediately after an interview with the USB still plugged in.

  5. Bluetooth wireless mics are not supported by this procedure unless they also show up as a USB audio device and pass the tap-test.

One-line summary

Phone-only video at the start and end for acoustic proof; USB mic only in the middle for interviews, after the meters prove the lav is live.