: If Stereo Mix isn't available, Audacity (a free, open-source tool) uses a host called Windows WASAPI . In Audacity, set the Audio Host to Windows WASAPI .

Right-click an empty area, select , and if Stereo Mix appears, right-click to Enable it.

Recording audio on your computer typically brings to mind a microphone, but what if you want to capture the crisp, digital sound of a YouTube video, a live stream, or a gameplay session without external noise interference? You can bypass the microphone entirely by using internal "loopback" methods to record the system audio directly. 1. Windows: The "Stereo Mix" and WASAPI Methods

: This is a virtual recording device provided by your sound drivers.

Once enabled, any recording app like the Windows Sound Recorder can use it as the "Microphone" source.

Choose your primary output device (e.g., Speakers) followed by as the recording device. This captures exactly what you hear. 2. Mac: Virtual Audio Drivers

Unlike Windows, macOS does not have a native "Stereo Mix" feature for internal audio recording. You'll need a "virtual cable" to bridge the gap. How to Record Internal Audio on Mac? - Apple Community