How to Manage Multiple Audio Streams with DS WASAPI ASIO Router Mixer

To route and mix WASAPI (the standard Windows audio protocol) and ASIO (professional low-latency audio) inputs simultaneously, you must bridge them. By default, Windows does not allow native simultaneous mixing of these protocols because ASIO bypasses the Windows mixer entirely to achieve low latency.

You can accomplish this through software routers, virtual audio bridges, or specialized hardware. Method 1: Using VB-Audio Matrix (Recommended)

VB-Audio Matrix is a modern routing application designed exactly for managing multiple ASIO, WASAPI, and WDM applications channel by channel. Install Matrix: Download and install VB-Audio Matrix.

Assign Physical Inputs: Open the Matrix grid. Assign your WASAPI audio device (like a USB microphone) to a physical input slot, and your professional audio interface to an ASIO slot.

Route to a Unified Output: In the visual grid matrix, click the connection points to route the audio channels from both your WASAPI device and your ASIO device into a single virtual output stream (e.g., Virtual ASIO ⁄₂).

Configure your DAW / Streaming App: Open your Digital Audio Workstation (DAW) or broadcasting software (like OBS). Set its audio device to the VB-Audio Matrix Virtual ASIO driver. You will now receive both sources mixed or split onto different tracks. Method 2: Using Voicemeeter Banana or Potato

Voicemeeter is a donationware virtual mixer that accepts multiple hardware inputs across different Windows driver types. Wasapi and external audio card – Cantabile Community

Lee only needed the same stereo output from Cantabile going out both an ASIO interface AND from a WASAPI/WDM one at the same time, Cantabile Community ASIO backend · Issue #67 · dechamps/FlexASIO – GitHub