WASAPI vs MME vs ASIO in Audacity
- Windows WASAPI
- Recommended. Low latency, high quality, supports loopback recording of system audio.
- MME
- Default. Compatible with all devices but higher latency. Use if WASAPI causes issues.
- Windows DirectSound
- Legacy. Similar to MME, rarely needed.
- ASIO
- Professional. Requires a dedicated audio interface with ASIO driver. Lowest latency.
| Host | Latency | Loopback | Use when |
|---|---|---|---|
| WASAPI | Low | Yes | Most users — recommended default |
| MME | High | No | Compatibility fallback |
| ASIO | Very low | No | Professional audio interfaces |
Set up WASAPI in Audacity
- 1
Open Preferences
Edit → Preferences (or Ctrl+P) → click Devices in the left panel.
- 2
Set Host to Windows WASAPI
In the Interface section, change the Host dropdown from MME to Windows WASAPI.
- 3
Select your recording device
In the Recording section, select your microphone or input device. For loopback recording (recording what you hear), select a device ending in (loopback).
- 4
Click OK and test
Click OK. Press the record button to test. You should see the waveform appear as you speak or play audio.
Record system audio with WASAPI loopback
WASAPI loopback lets you record whatever is playing through your speakers — music, video, system sounds:
- Set Host to Windows WASAPI
- Set Recording device to your output device followed by (loopback), e.g. "Speakers (loopback)"
- Press Record — Audacity captures all system audio
Fix WASAPI problems in Audacity
WASAPI questions
Windows WASAPI Audacity — why is it better than MME?
WASAPI communicates directly with Windows audio engine, bypassing the mixing layer that MME uses. This results in lower latency, better sample accuracy and support for loopback recording. MME is a legacy interface from the Windows 9x era and has higher latency.
WASAPI recording problems — microphone not working
Check: (1) Windows microphone permissions — Settings → Privacy → Microphone → allow Audacity. (2) The correct input device is selected in Audacity Preferences → Devices. (3) The device is not set to exclusive mode in Windows Sound settings.