Audacity WASAPI Loopback Not Working: How to Fix It

Windows WASAPI loopback lets Audacity record the sound your computer is playing, such as a video call, a browser tab or another app, without a cable or a microphone. When it fails, the cause is usually the device selection, a format mismatch with Windows, or the audio being sent to a different output than the one Audacity is listening to. This guide covers Audacity on Windows only, because WASAPI is a Windows audio interface.

Identify the symptom and environment

Before changing anything, write down what you see. Different symptoms point to different causes, and you will need these notes if the problem persists.

• Audacity shows an error when you press Record, for example an error about opening the recording device or an invalid sample rate.
• Recording starts but the waveform stays flat even though you can hear audio.
• The recording timeline stalls or does not advance until something plays.
• No loopback entry appears in the recording device list at all.
• The recording works with one output, such as speakers, but not with another, such as a USB or Bluetooth headset.

Also note your Audacity version (shown in the About dialog), your Windows version, the playback device you are listening on, and whether the problem started after an update, a new headset or a change in Windows sound settings.

Isolate where the fault occurs

Loopback capture depends on three things lining up: the app playing sound, the Windows output device that receives it, and the loopback device Audacity records from. Check each link separately.

• Output path: play audio and confirm you actually hear it. In Windows, check which device is the default output and whether the app you want to record has been assigned to a different output in the per-app volume or device settings.
• Audacity host: confirm the audio host in Audacity is set to Windows WASAPI. Loopback devices only appear under that host, not under MME or DirectSound.
• Device match: the loopback device must correspond to the output that is playing the sound. Recording the speakers loopback while audio goes to a headset captures nothing.
• Audacity input in general: switch to a microphone under the same WASAPI host and try a short recording. If that also fails, the issue is broader than loopback.
• Other capture method: if your sound driver exposes a Stereo Mix input, a quick test with it can show whether system audio reaches the capture side at all. It is optional and not available on every system.

Windows microphone privacy settings control access to input devices. If Audacity cannot open any recording device, including a microphone, check that desktop apps are allowed to use the microphone. If only the loopback entry fails, privacy settings are a less likely cause.

Try reversible fixes in order

Work through these in sequence and test after each one. Menu names vary between Audacity versions: recent releases put device selection behind an Audio Setup button on the toolbar and in an Audio Settings page in Preferences, while older releases use a Device Toolbar and a Devices page.

1. Select the correct host and loopback device

Set the host to Windows WASAPI, then pick the recording device whose name matches your current playback device and is marked as loopback. Set the playback device in Audacity to the same output. Expected result: when audio plays and you click the recording meter to start monitoring, the meter moves.

2. Rescan devices after hardware changes

If you plugged in a headset or changed the default output while Audacity was open, the device list may be stale. Use the Rescan Audio Devices command (found in the Transport menu in many versions) or restart Audacity, then reselect the loopback device.

3. Match the project sample rate to the Windows format

WASAPI loopback in shared mode records at the format Windows uses for that output. If the Audacity project rate differs, recording can fail with a sample rate error or produce nothing. Open the classic Sound control panel (in Windows 11 it is reachable through More sound settings), go to the Playback tab, open the properties of your output device and read the Default Format on the Advanced tab. Set the Audacity project sample rate to the same value, for example 48000 Hz if Windows shows 48000 Hz. Changing the Audacity project rate is the simpler and more reversible choice than changing the Windows format.

4. Use matching recording channels

Most outputs are stereo. If the recording channel setting in Audacity is mono and the device rejects it, set recording channels to 2 (Stereo) in the audio settings and try again.

5. Make sure audio is actually playing

Loopback only receives data when the output is producing sound. On some versions the recording may appear to stall or capture nothing during silence. Start playback in the source app first, or keep it playing, before pressing Record.

6. Release exclusive control of the output

If another app has taken exclusive control of the output device, loopback capture may fail. In the same device properties dialog, the Advanced tab has options for allowing applications to take exclusive control. Temporarily clearing them, or closing the app that holds the device, is a reversible test. Restore the original setting afterwards if you rely on exclusive mode elsewhere.

7. Turn off software playthrough

If software playthrough is enabled in Audacity recording settings, it can feed the captured audio back to the same output and cause echo or feedback. Turn it off for loopback recording.

8. Check Bluetooth headset mode

Bluetooth headsets often appear as two separate outputs, one for stereo playback and one for hands-free use with the microphone. During a call, Windows may switch audio to the hands-free output. Pick the loopback device that matches the output currently carrying the sound.

Some playback paths, such as certain protected media, may deliver silence to capture tools by design. If only one specific app records silently while others work, that limitation is a possible explanation rather than an Audacity fault.

Confirm the result

Play a short, recognizable clip from the same app that failed before. Record ten to twenty seconds, stop, and check that the waveform shows activity and that playback in Audacity sounds like the source. Repeat once with the setup you normally use, for example during a real call or with your usual headset, because a fix on speakers does not prove the headset path works. If you changed any Windows device option only for testing, put it back and confirm the recording still works.

If the problem remains

Keep a short record of what you observed: Audacity version, Windows version, the exact text of any error, the host and devices selected, the project rate and the Windows Default Format, and which tests succeeded, such as a microphone under WASAPI or a different output device. These details make a support request or community forum post far more useful.

If loopback fails only with one output device while others work, the device driver or its software is the likely area to examine, and the device maker's support is the right contact. Use drivers from the device or computer manufacturer rather than unknown download sites. If loopback fails with every output and every app, ask in Audacity's official support channels with your notes. A failed loopback recording on its own is not evidence of broken hardware, so avoid factory resets or replacing equipment until the steps above have narrowed down the cause.