Audacity Not Recording Stereo Mix: How to Fix It

Stereo Mix is a recording input that some Windows audio drivers provide so programs can capture the sound your computer is playing. When Audacity won't record it, the cause is usually routing or settings, not broken hardware. This guide helps you find where the signal stops and fix it with changes you can easily undo.

Identify the symptom and environment

Stereo Mix is a Windows feature. macOS and Linux handle system audio capture differently, so these steps assume Windows 10 or Windows 11. Before changing anything, write down exactly what happens. The symptoms point to different causes:

• Stereo Mix does not appear in Audacity's recording device list at all.
• Stereo Mix appears, but Audacity shows an error when you press Record.
• Recording starts, but the waveform is a flat line and the meter does not move.
• The recording contains your microphone or room sound instead of computer audio.
• Recording worked before and stopped after a Windows update, a driver update or a new headset or monitor.

Also note your Audacity version (shown in Help > About Audacity) and which audio output you are listening through, such as built-in speakers, a USB headset, Bluetooth headphones or an HDMI monitor. The output matters, as the next section explains.

Isolate where the fault occurs

Test each layer separately so you know whether to fix Windows, the driver or Audacity.

First, check whether Windows sees Stereo Mix. Open the classic Sound control panel. In recent Windows versions it is linked from Sound settings, labelled More sound settings or Sound Control Panel depending on the version. You can also run mmsys.cpl. Go to the Recording tab. If Stereo Mix is not listed, right-click an empty area and enable both Show Disabled Devices and Show Disconnected Devices. If it still does not appear, your current driver may not provide it. Some generic or vendor drivers never include it.

Next, check whether Stereo Mix receives any signal. With the Recording tab open, play audio in any app. The level bar next to Stereo Mix should move. If it stays still, Audacity is not the problem. A common reason is that Stereo Mix only captures audio going to the output it is paired with, usually the onboard speaker or headphone jack. Sound sent to a USB headset, Bluetooth device or HDMI monitor bypasses it and leaves Stereo Mix silent.

If the Windows meter moves but Audacity records nothing or shows an error, the problem is in Audacity's device selection, Windows privacy permissions or a format or exclusive-access conflict.

Try reversible fixes in order

Work through these steps in order and test after each one. Every change can be reverted.

1) Enable Stereo Mix. In the Recording tab, right-click Stereo Mix and choose Enable if it is disabled. Then open its Properties and check the Levels tab. Make sure the level is not at zero and the input is not muted.

2) Match the playback output. If you listen through a headset or HDMI, Stereo Mix may stay silent. For a test, switch playback to the onboard output in Windows. If that fixes it, either keep using that output while recording or use the loopback method in step 6, which captures whichever output you actually use.

3) Check microphone privacy permissions. In Windows 11, go to Settings > Privacy & security > Microphone. In Windows 10, go to Settings > Privacy > Microphone. Make sure microphone access is on and that desktop apps are allowed to use it. Windows applies this permission to recording inputs in general, so it can block Stereo Mix as well as a physical microphone.

4) Select the device in Audacity and rescan. Audacity 3.2 and later use an Audio Setup button on the toolbar, with Host, Recording Device and Recording Channels options plus a Rescan Audio Devices command. Older versions use a Device Toolbar with drop-down lists and offer Rescan Audio Devices in the Transport menu. Audacity may not notice a device you just enabled until you rescan or restart it. Choose Stereo Mix as the recording device rather than a generic mapper entry, which follows the Windows default input. Set recording channels to 2 (stereo).

5) Try a different host. Audacity on Windows usually offers MME, Windows DirectSound and Windows WASAPI. Device names, and whether a device opens without errors, can differ between hosts. If Stereo Mix fails under one host, select it under another and test again.

6) Use WASAPI loopback instead of Stereo Mix. Set the host to Windows WASAPI, then open the recording device list. Audacity lists your playback devices with "(loopback)" after the name. Pick the loopback entry for the output you actually listen through. This captures that output directly. It does not need Stereo Mix, so it also works with headsets and HDMI. If loopback records correctly, you can rely on it and leave Stereo Mix alone.

7) Resolve sample rate and exclusive-mode conflicts. If Audacity reports an error opening the device, open Stereo Mix Properties and check the Default Format on the Advanced tab. Set Audacity's project sample rate to the same value. In newer versions the project rate is in the audio settings preferences; older versions show it in the lower-left corner of the window. If error messages continue, you can temporarily untick the options that let applications take exclusive control. Do this on the Advanced tab of both Stereo Mix and your playback device. Note the original settings so you can restore them.

8) Check the source app. Some apps output audio in ways that loopback capture may not pick up, and some protected streams may block capture. If one app records silence while others record fine, the limitation is likely in that app, not in Audacity or Stereo Mix.

Confirm the result

Play a short, recognizable sound, such as a song with a clear left-right stereo image. Before recording, click Audacity's recording meter to start monitoring. The meter should respond to the playback. Record 10 to 20 seconds, stop and play it back.

• The waveform is visible and not a flat line.
• Both stereo channels contain audio.
• The recording contains only computer audio, with no room noise or voice from a microphone.
• The level is not clipping constantly; lower the source volume if peaks hit the top of the meter.

If you hear echo or repeated audio while recording, check whether software playthrough is turned on in Audacity's transport or recording options. Playthrough can feed the recording back into the output. Finally, restart the computer and repeat the short test to confirm the device selection and Windows settings persist.

If the problem remains

Keep a short record of what you observed. It makes support requests much faster:

• Windows version and Audacity version.
• The host and recording device selected in Audacity.
• The exact error message text, if any.
• Whether the Stereo Mix meter moves in the Windows Recording tab.
• Whether WASAPI loopback records correctly.
• Which playback output you use and whether the issue began after a specific update or hardware change.

If Stereo Mix is missing even with hidden devices shown, the audio driver most likely does not provide it. Check the support pages from your computer or motherboard manufacturer for the driver intended for your model. Avoid driver packages from unknown sources. If WASAPI loopback works, you may not need Stereo Mix at all. If neither Stereo Mix nor loopback ever shows a signal while normal playback sounds fine, ask the device maker's support or the Audacity community, using the notes above. A silent capture input is rarely proof of failed hardware; routing, driver features and permissions are far more common causes.