How to Record Desktop (Computer) Audio on Windows

Short version: To record the sound coming out of your PC, capture system (loopback) audio — a recorder that supports loopback grabs whatever’s playing through your speakers, no mic needed. Add your microphone as a second input if you want to narrate. Older tools may need Stereo Mix enabled in Windows sound settings.

“Desktop audio” (also called system or internal audio) is the sound your computer produces — a video, a game, a call, an app alert — as opposed to what your microphone hears. Capturing it cleanly is a common sticking point on Windows. Here’s how.

System audio vs. microphone

Two separate sources:

• System / desktop audio — the output, everything playing through your speakers.
• Microphone — the input, your voice and room.

You might want one, the other, or both mixed. Getting this choice right is the whole game.

The modern way: loopback capture

Windows can expose its own audio output as something recordable (“loopback”). A recorder that supports loopback capture grabs system sound directly — no extra setup, no microphone bleed. Pick system audio as the source, play what you want, and it’s captured cleanly.

The older way: Stereo Mix

Some tools rely on Stereo Mix, a legacy input that mirrors your speaker output:

1. Right-click the speaker icon → Sound settings → More sound settings.
2. On the Recording tab, right-click an empty area → Show Disabled Devices.
3. Enable Stereo Mix and set it as the input in your recorder.

Not every sound card exposes Stereo Mix, which is exactly why direct loopback is the better approach when your tool supports it.

Adding your microphone

To narrate over the system sound, select your mic as a second input so both are recorded and mixed in sync. Keeping them lined up (and padding silence during pauses) is where a purpose-built recorder beats piecing it together by hand — the same challenge covered in how to record system audio and your mic together.

If it comes out silent

• Recording the mic instead of system audio — switch the source.
• Wrong playback device selected — match it to where the sound is actually going.
• DRM-protected media (some streaming apps) blocks capture on purpose — that can’t be bypassed, and this guide isn’t about doing so. And if you’re recording a call, get everyone’s consent first.

Doing it with KeepCast

KeepCast is a local-first screen recorder for Windows that captures system (loopback) audio and your microphone together, in sync, with no Stereo Mix fiddling — as a video (MP4) when you’re recording the screen, and you can detach the audio in the editor if you only want the sound. Everything stays on your machine, no upload, no watermark. (Join the waitlist.) If you only need the audio out of a video you already have, see how to extract audio from a video.

The bottom line

Recording desktop audio comes down to choosing the right source: system/loopback for the sound your computer makes, plus the microphone if you’re narrating. Modern recorders capture loopback directly; older ones need Stereo Mix. Get the source right and the “why is it silent?” problem disappears.