How to Connect a Virtual Audio Mixer to OBS

Before you start

This process runs locally on the computer where OBS Studio is installed. You need a virtual audio device installed on the same machine, such as a virtual audio cable or virtual mixer, plus OBS Studio with access to its audio settings. Close any programs that may lock audio devices during installation, and have a short test source ready: a music player, browser tab, game, or microphone.

Avoid testing with sensitive audio until the signal path is working. The virtual mixer should be installed and visible to the operating system before you open OBS. If it was just installed, restart OBS so the new input device and output device appear in the audio device lists.

Step-by-step instructions

The goal is to send one or more programs into the virtual mixer, then bring that mixed signal into OBS as a controlled audio source. Start from the operating system sound settings and finish in OBS.

• 1. Set the virtual mixer or audio cable as an output device for the application you want to capture. On Windows, you can change this per app under Sound settings; on macOS, use an app such as a virtual audio driver that supports creating a virtual output device.
• 2. Open OBS and go to Settings, then Audio.
• 3. Under Global Audio Devices, keep the desktop and microphone devices suitable for your normal setup, or set them to Disabled if you plan to use only explicit audio capture sources.
• 4. Return to the main OBS window and add an Audio Input Capture source for a microphone routed through the mixer, or an Audio Output Capture source for desktop application audio sent to the virtual output device.
• 5. Choose the virtual mixer device as the source device. On Windows, an Audio Output Capture source can monitor the virtual output device that your application is using.
• 6. Check Input Level in the OBS audio mixer while your test sound is playing. Raise or lower the level inside the virtual mixer, then make fine adjustments with the OBS mixer slider.

If the virtual mixer exposes separate channels, assign each channel to its own OBS source instead of mixing everything into one input. This gives independent volume control and easier correction if one capture source becomes too quiet or noisy.

Keep sample rate settings consistent. In OBS, the audio sample rate and the virtual device sample rate should match where the driver allows it. A mismatch can still work, but may cause drift or resampling depending on the operating system and driver.

Check the output

Play a known test sound and confirm that the OBS audio meter moves for the intended source only. The meter should return near silence when the source is muted in the virtual mixer. Listen through OBS monitoring only if you have headphones connected, because direct monitoring of a virtual output can create an echo when the same signal is also captured.

Make a short local recording and play it back. Check that speech remains intelligible, music is not heavily distorted, and background noise is at an acceptable level. OBS records using the configured audio encoding and bitrate; a higher audio bitrate generally preserves more detail but increases file size.

Common problems and next steps

No meter movement often means the wrong device was selected in OBS or the application is still sending audio to a different output device. Confirm both places use the same virtual mixer device, then restart the application after changing its output setting.

An echo or doubled signal usually appears when OBS captures the same audio through both Desktop Audio and an explicit capture source. Disable one path and leave only the virtual mixer source active. If the tone is unusually high or slow, compare the device sample rate with the OBS sample rate and set them to the same value where possible.

For background noise, first reduce gain in the virtual mixer and keep the OBS input level below clipping. You can then add an OBS noise suppression filter to the affected source. When the mix is stable, adjust recording format, audio bitrate, and encoding from the Output settings before starting a stream or long recording.