Virtual Audio Routing for Internet Radio: VB-Audio Virtual Cable with PlayoutONE

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Virtual audio routing is one of those concepts that sounds technical but is straightforward once you understand what it actually does. It solves a specific problem: PlayoutONE plays audio on your PC, and LiveStream needs to receive that audio to encode and stream it to your listeners. How do you connect them without running a physical cable from one audio port to another?

The answer is a virtual cable — software that creates an internal audio connection between two applications. PlayoutONE sends audio into one end, LiveStream receives it from the other, and no physical cables, microphone inputs, or sound cards are involved. The result is cleaner audio, better isolation from Windows system sounds, and a more reliable broadcast chain overall.

This guide is part of the Complete Guide to Building a 24/7 Internet Radio Station with PlayoutONE.

Why Not Just Use a Physical Cable?

Some beginners try to route audio from the PC’s headphone output into the microphone input using a physical 3.5mm cable. It works, in the sense that audio gets from one place to another — but it introduces several problems:

  • Noise. Running audio through a D/A converter (headphone out) and then an A/D converter (mic in) introduces generation loss and often picks up electrical noise from the PC’s internals.
  • Level matching. Headphone outputs and microphone inputs operate at very different signal levels. Getting the levels right without distortion or a very weak signal requires precise gain matching.
  • No isolation. A physical loopback does nothing to isolate your broadcast audio from Windows system sounds on the same device.
  • Reliability. Physical cables and connectors can work loose, corrode, or fail. A software virtual cable has no physical components to fail.

Virtual audio cable solves all of these problems at once.

The Recommended Tool: VB-Audio Virtual Cable

VB-Audio Virtual Cable is the industry standard for this task. It is free for personal use, stable, and widely used by internet radio broadcasters, podcasters, streamers, and professional audio engineers.

Download it from the official VB-Audio website:

https://vb-audio.com/Cable/

VB-Audio operates on a donationware model — it is free to use, but the developer accepts voluntary contributions. If it becomes a permanent part of your broadcast chain (and it will), consider supporting the project.

Installing VB-Audio Virtual Cable

  1. Download the installer from the VB-Audio website
  2. Extract the ZIP file
  3. Right-click the installer (VBCABLE_Setup_x64.exe for 64-bit systems) and select Run as administrator — this is required for the driver to install correctly
  4. Click Install Driver
  5. Accept any driver installation prompts from Windows
  6. Restart your PC after installation completes

After the restart, VB-Audio Virtual Cable appears in Windows as two audio devices: CABLE Input (a virtual speaker/output) and CABLE Output (a virtual microphone/input). These are the two ends of the internal pipe between your applications.

Understanding How the Routing Works

Think of VB-Audio as a pipe with two ends:

  • CABLE Input is the entry point — the “speaker” side. Whatever audio you send here goes into the pipe.
  • CABLE Output is the exit point — the “microphone” side. Whatever you connect here receives the audio coming through the pipe.

Your broadcast chain looks like this:

PlayoutONE  →  CABLE Input  →  [virtual pipe]  →  CABLE Output  →  LiveStream

PlayoutONE sends its audio output to CABLE Input. LiveStream picks up audio from CABLE Output. The audio travels internally through the driver without touching your physical speakers or any external hardware.

Configuring PlayoutONE to Use the Virtual Cable

  1. Open PlayoutONE
  2. Navigate to Settings → audio output configuration
  3. You will see options for your output devices — look for a broadcast output or stream output setting (separate from your monitor/speakers output)
  4. Set the broadcast output to CABLE Input (VB-Audio Virtual Cable)
  5. Leave your monitor output set to your actual speakers or headphones — this is what you hear in the room

PlayoutONE now sends two audio streams: one to your physical speakers for monitoring, and one to the virtual cable for LiveStream to pick up.

Configuring LiveStream to Receive from the Virtual Cable

  1. Open LiveStream
  2. Navigate to the audio input settings
  3. Set the audio input source to CABLE Output (VB-Audio Virtual Cable)

LiveStream now receives its audio from the virtual cable output — which is exactly what PlayoutONE is sending.

Setting the Correct Sample Rate

For clean audio transfer through the virtual cable, both applications should agree on sample rate. Mismatched sample rates cause pitch drift, distortion, or crackling.

  1. Open Control Panel → Sound
  2. Find CABLE Input in the Playback tab — right-click → Properties
  3. Go to the Advanced tab
  4. Set the format to 2 channel, 16 bit, 44100 Hz (CD Quality) or 48000 Hz — whichever matches your PlayoutONE and LiveStream settings
  5. Repeat for CABLE Output in the Recording tab

44100 Hz is standard for most music content. 48000 Hz is common in professional broadcast environments. Pick one and use it consistently across all devices and applications in your signal chain.

Testing the Routing

Before configuring LiveStream with your actual streaming credentials, test that audio is flowing through the virtual cable correctly.

  1. Play a track in PlayoutONE
  2. Open Windows Sound Settings → Sound Control Panel → Recording tab
  3. Find CABLE Output in the list
  4. Watch the level meter next to CABLE Output — it should be moving when audio plays in PlayoutONE

If the meter moves, audio is flowing through the virtual cable correctly. If it does not move, check that PlayoutONE’s broadcast output is set to CABLE Input, and that audio is actually playing (not paused or muted).

The Critical Warning: Never Create an Audio Loop

An audio loop happens when the output of a system is fed back into its own input, creating a feedback cycle. In broadcast audio, this sounds like a howling feedback tone that immediately takes your stream down.

The way this happens in PlayoutONE setups:

  • LiveStream is configured to both receive from CABLE Output and output back to CABLE Input
  • Or a monitoring application accidentally routes CABLE Output back to CABLE Input

Check your routing carefully:

  • PlayoutONE output → CABLE Input ✓
  • LiveStream input → CABLE Output ✓
  • LiveStream output → your streaming server ✓ (NOT back to CABLE Input)

If you ever hear a sudden screech or howl on your stream, an audio loop is the most likely cause. Kill LiveStream first to break the loop, then audit your routing.

Troubleshooting Common Routing Problems

Audio plays in PlayoutONE but LiveStream receives silence

  • Confirm PlayoutONE’s broadcast output is CABLE Input (not your speakers)
  • Confirm LiveStream’s input is CABLE Output (not your microphone)
  • Check the CABLE Output level meter in Windows Sound as described in the testing section

Audio sounds distorted or the pitch is wrong

  • Check sample rate consistency — CABLE Input, CABLE Output, PlayoutONE, and LiveStream should all be set to the same sample rate

CABLE devices are not appearing in the device list

  • Confirm you ran the VB-Audio installer as Administrator
  • Restart the PC — the driver requires a full reboot to appear
  • Check Device Manager for any driver errors under Sound, video and game controllers

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