Understanding the Audio Conflict
Pro Tools relies heavily on low-latency audio drivers, typically ASIO, to ensure precise timing during recording and mixing. These drivers often require exclusive access to specific hardware interfaces to minimize buffer latency. When you attempt to use ShareX for video recording, it defaults to capturing "Desktop Audio" using the standard Windows DirectSound or WDM-KS APIs. This default behavior frequently causes conflicts because the operating system struggles to route the same audio stream to both the high-performance ASIO interface and the screen recording application.
Without a virtual intermediary, enabling desktop audio in ShareX may cause Pro Tools to lose its connection to the audio interface, resulting in silence, crackling, or the application crashing entirely. The core issue is not that ShareX cannot record, but that it hijacks the primary audio output device. To fix this, we need to introduce a virtual cable that acts as a bridge, allowing the system audio to be sent to ShareX while leaving the physical interface free for Pro Tools.
Installing the Virtual Loopback Driver
The most reliable solution involves installing a virtual audio cable driver. VB-Audio Virtual Cable is a popular, free option that integrates seamlessly with Windows. Begin by downloading the installer from the official VB-Audio website. Run the installer as an administrator to ensure all necessary kernel-level filters are registered correctly. During installation, accept the default settings unless you have specific requirements for multiple virtual channels.
Once installed, you should see two new devices in your Windows Sound settings: "CABLE Input" and "CABLE Output." These represent the virtual loopback path. The "Output" sends audio into the cable, and the "Input" receives audio from it. You do not need to physically connect anything; this is purely a software-based routing mechanism. Verify the installation by checking the Device Manager under "Sound, video and game controllers" to ensure the virtual cable driver is active and has no warning icons.
Configuring Windows Audio Routing
After installation, you must redirect your system's primary audio output to the virtual cable. Open the Windows Settings app and navigate to System > Sound. Under the Output section, change the selected device from your physical speakers or headphones to "CABLE Output (VB-Audio Virtual Cable)." This step is critical because it ensures that all desktop audio generated by your computer, including media players, browser tabs, and system notifications, is routed into the virtual cable instead of your physical speakers.
You will notice that you can no longer hear audio through your physical speakers if they are not also configured to receive this signal. To maintain monitoring capabilities, you can enable "Listen to this device" on the CABLE Input device in the classic Control Panel sound settings, routing the audio back to your headphones if needed. However, for the purpose of ShareX recording, the primary goal is simply to get the audio into the virtual cable. If you encounter issues with other applications failing to find an audio device, ensure that Windows is not attempting to force exclusive mode on any remaining physical devices.
Setting Up ShareX
With the virtual cable in place, open ShareX and navigate to Settings > Capture > Audio. In the Desktop Audio section, select "CABLE Input (VB-Audio Virtual Cable)" as the source. Do not leave this set to "Default" or your physical microphone, as that will not capture the system audio you just routed. Ensure that the sample rate matches your project settings, typically 48kHz or 44.1kHz, to avoid pitch issues in your final video.
If you are recording gameplay or software demonstrations where microphone commentary is also required, you can add a second audio track for your microphone. Set the Microphone input to your actual USB or XLR microphone interface. This dual-track approach allows you to mix desktop audio and voiceover separately in post-production. Test the configuration by starting a short screen recording. Play a video file on your desktop and check the waveform in ShareX after stopping the recording. You should see a clear audio track corresponding to the desktop sounds.
Integrating with Pro Tools
Now that ShareX is configured, return to Pro Tools. Ensure that your I/O setup still points to your physical audio interface. Since the virtual cable is now handling the desktop audio output, Pro Tools should regain exclusive control over the ASIO driver without interruption. You can verify this by opening a session in Pro Tools and checking the engine status. It should report no latency errors or driver conflicts.
If you experience glitches when switching between Pro Tools and other applications, consider adjusting the buffer size in Pro Tools. Higher buffer sizes provide more stability for complex sessions, while lower buffers are better for real-time monitoring. The virtual cable adds negligible latency, so it should not impact your ability to record at low buffer settings. For more details on managing long recordings and playback issues, you might find ShareX: Recorded Long Video Not Fast Forwarding - Troubleshooting helpful for optimizing storage and performance.
Troubleshooting Common Issues
If ShareX records silence despite correct configuration, verify that the volume slider for "CABLE Input" is unmuted in the Volume Mixer. Right-click the speaker icon in the taskbar and select Volume Mixer. Ensure that the applications playing audio are sending their sound to "CABLE Output" and that the master volume for the cable is turned up. Additionally, some applications allow you to manually select their audio output device; ensure these are set to the virtual cable rather than your default speakers.
If Pro Tools crashes upon launching ShareX, ensure that no other virtual audio drivers like VoiceMeeter or SteelSeries Engine are conflicting. Having multiple virtual audio engines active can cause driver signature verification failures or resource exhaustion. Disable any unused virtual audio devices in Device Manager. Also, check that ShareX is updated to the latest version, as older builds may have compatibility issues with newer Windows audio stack updates.
Frequently Asked Questions
Can I use Voicemeeter instead of VB-Cable?
Yes, Voicemeeter Banana or Potato is a powerful alternative that offers more advanced mixing capabilities. However, it requires more complex configuration to isolate the virtual output for ShareX. VB-Cable is generally simpler for users who only need a basic loopback solution without extensive routing matrices.
Does this setup increase CPU usage significantly?
No, virtual audio cables consume negligible CPU resources. They operate at the kernel level and simply pass data streams between applications. The primary CPU load will come from ShareX encoding the video and Pro Tools processing audio plugins, not from the virtual cable itself.
What if my microphone picks up the desktop audio through the cable?
This can happen if you route the CABLE Output back to your microphone input. To prevent feedback loops, ensure that your microphone input is isolated. In ShareX, keep the microphone input separate from the desktop audio input. Use hardware noise gates or software suppression in Pro Tools to filter out any accidental bleed.
Will this work on macOS?
The steps described are specific to Windows. On macOS, you would use BlackHole or Loopback to achieve similar results. The principles remain the same: create a virtual aggregate device that captures system audio and routes it to your recording software.
How do I switch back to normal audio listening?
To return to normal audio, simply change your Windows Output device back to your physical speakers or headphones in System > Sound. All applications will resume playing audio through your default hardware. You do not need to uninstall the virtual cable.