Low-pass-filtered sound when recording stereomix

Hello audacitizen,

I started recording music from my sound card (stereomix) using audacity. The result sounds like it has been low-pass-filtered because it hasn’t any high-pitched sounds. I have no idea where this effect comes from. I tried to record inner sounds with an other software → same result! Does anybody have an idea how to fix this problem?


Turn off sound effects in your sound card (probably in the sound card’s control panel).

Make sure you really are selecting stereo mix by name as the Audacity recording device, not Sound Mapper - Input or Primary Sound Capture Driver. Those are whatever the default Windows recording device is at the time, which might not be stereo mix.

In any case you are probably better to record using Windows WASAPI (loopback), which captures the stream digitally, bypassing the lossy steps of converting to analogue to play the sound then back to digital: http://manual.audacityteam.org/man/tutorial_recording_computer_playback_on_windows.html#wasapi .


Thank you for your answer. I turned off every sound manipulation option in the soundcard panel but the problem still remains. Maybe there is another sound system panel somewhere else that is influencing the sound. The weird thing is that the sound coming out of my laptop speakers is fine… The problem only occurs when listening to the recorded tape.

In your first message you said you were recording computer playback. Are you now recording cassettes? That is a different problem.

If you clarify what you are trying to achieve we may be able to help you better.


No, just computer playback. Nothing else.


Have you tried WASAPI loopback as previously suggested, rather than stereo mix?

  1. In Audacity, open Device Toolbar.
  2. In the first (Host) box of Device Toolbar, choose “Windows WASAPI”.
  3. In the second (Recording Device) box, choose the (loopback) input for the device you are using for playback. For example, if you are using “Speakers” for listening to playback, choose “Speakers (loopback)” in this step.
  4. In the third (Recording Channels) box, choose mono or stereo.
  5. In the fourth (Playback Device) box, choose the Speakers that you are using for listening.
  6. Start playing the audio you want to record.
  7. Press the big red Record button in Audacity.