No Audio Devices

Audio devices not appearing in the device selection dropdown.

Symptoms

• System Audio Device dropdown shows "none" or is empty
• Microphone Device dropdown shows no devices
• "Refresh Devices" doesn't populate the list
• Error message: "No audio devices found"

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Common Causes

Windows

Cause	Solution
VB-Cable not installed	Install VB-Cable
FFmpeg not working	Check FFmpeg
Windows audio permissions	Enable microphone access
Device enumeration failed	Restart application

macOS

Cause	Solution
FFmpeg not installed	Install FFmpeg
Microphone permission denied	Grant microphone access
BlackHole not installed	Install BlackHole
FFmpeg lacks AVFoundation	Reinstall FFmpeg

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Windows Solutions

Install VB-Cable

VB-Cable is required for capturing system audio.

1. Download from vb-audio.com/Cable
2. Extract the ZIP file
3. Right-click VBCable_Setup_x64.exe → Run as Administrator
4. Click Install
5. Reboot your computer
6. Check Windows Sound Settings → "CABLE Input" and "CABLE Output" should appear

Reboot Required

VB-Cable requires a reboot to work properly.

Check FFmpeg

Intervu uses FFmpeg to enumerate audio devices.

1. Open Settings (gear icon)
2. Check for FFmpeg error message
3. If error, the bundled FFmpeg may not have downloaded

Manual FFmpeg fix:

# Check if FFmpeg exists
dir %LOCALAPPDATA%\intervu\ffmpeg.exe

# If missing, try reinstalling the app
# Or set a custom FFmpeg path in Settings

Using system FFmpeg:

If you have FFmpeg installed system-wide:

1. Open Settings
2. Go to Advanced Settings
3. Set FFmpeg Path to your FFmpeg location
   • Example: C:\ffmpeg\bin\ffmpeg.exe

Enable Microphone Permissions (Windows)

Windows may block microphone access.

1. Open Settings → Privacy → Microphone
2. Enable "Allow apps to access your microphone"
3. Enable "Allow desktop apps to access your microphone"
4. Restart Intervu

Refresh Devices

1. Open Settings (gear icon)
2. Click Refresh Devices
3. Wait for enumeration (may take a few seconds)

Restart Application

Sometimes Windows audio system needs a refresh:

1. Close Intervu completely
2. Open Windows Sound Settings
3. Verify devices appear in Windows
4. Restart Intervu

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macOS Solutions

Install FFmpeg (macOS)

FFmpeg is required on macOS and must be installed manually.

# Install via Homebrew
brew install ffmpeg

# Verify installation
ffmpeg -version

The FFmpeg path on macOS is typically:

• Intel Macs: /usr/local/bin/ffmpeg
• Apple Silicon Macs: /opt/homebrew/bin/ffmpeg

If Intervu still can't find FFmpeg:

1. Open Settings (gear icon)
2. Go to Advanced Settings
3. Set FFmpeg Path to /usr/local/bin/ffmpeg or /opt/homebrew/bin/ffmpeg

Verify AVFoundation support:

ffmpeg -f avfoundation -list_devices true -i ""

This should list available audio and video devices. If it fails, reinstall FFmpeg:

brew reinstall ffmpeg

Grant Microphone Access (macOS)

macOS requires explicit microphone permission for Intervu.

1. Open System Settings → Privacy & Security → Microphone
2. Find Intervu and enable it
3. If Intervu is not listed:
   • Open Intervu and click the microphone button
   • macOS will display a permission prompt
   • Click "Allow"
4. Restart Intervu

Install BlackHole

BlackHole is required for capturing system audio on macOS.

1. Download from existential.audio
2. Open the .pkg file and install
3. Reboot your Mac
4. Check System Settings → Sound → BlackHole should appear in Input/Output

Refresh Devices

1. Open Settings in Intervu
2. Click Refresh Devices
3. Wait for AVFoundation enumeration (may take a few seconds)

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Verifying Installation

Windows: VB-Cable

Open Settings → System → Sound:

• Playback: Should show "CABLE Input (VB-Audio Virtual Cable)"
• Recording: Should show "CABLE Output (VB-Audio Virtual Cable)"

macOS: BlackHole

Open System Settings → Sound:

• Input: Should show "BlackHole 2ch"
• Output: Should show "BlackHole 2ch"

Also verify multi-output device in Audio MIDI Setup.

Testing Audio Capture

Windows:

1. Play any audio on your computer
2. Set your speaker output to "CABLE Input"
3. Set another app (like Audacity) to record from "CABLE Output"
4. You should see the audio waveform

macOS:

1. Set system output to your multi-output device
2. Open Intervu Settings
3. Select BlackHole as System Audio Device
4. Play any audio — level meter should show activity

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Device Enumeration Details

What Intervu Looks For

Windows (DirectShow):

• Render devices: For system audio capture (CABLE Output)
• Capture devices: For microphone input

macOS (AVFoundation):

• All audio devices: Listed by FFmpeg with AVFoundation
• BlackHole: For system audio capture
• Physical microphones: For your voice input

FFmpeg Commands

Windows:

ffmpeg -list_devices true -f dshow -i dummy

macOS:

ffmpeg -f avfoundation -list_devices true -i ""

If either command fails, device enumeration will fail.

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Still Not Working?

Windows

Check Logs

1. Open Settings (gear icon)
2. Click Open Logs Folder
3. Check app.log for errors

Common Log Errors

[dshow] Could not find device

→ VB-Cable not installed or device name changed

ffmpeg: command not found

→ FFmpeg missing or path incorrect

Permission denied

→ Windows microphone permissions blocked

Reset Settings

# Close Intervu
# Delete settings
rmdir /s /q %APPDATA%\intervu
# Restart Intervu
# Reconfigure from scratch

macOS

See macOS Troubleshooting for macOS-specific issues.

Common macOS Log Errors

FFmpeg not found. Install via: brew install ffmpeg

→ FFmpeg is not installed or not in PATH

No audio devices found. Ensure FFmpeg is installed

→ FFmpeg lacks AVFoundation or microphone permission not granted

Microphone permission not granted

→ Grant permission in System Settings → Privacy & Security → Microphone

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Next Steps

• Audio Devices — Configure audio settings
• FFmpeg Errors — FFmpeg-specific issues
• macOS Setup — macOS audio setup guide
• macOS Troubleshooting — macOS-specific issues