Buzzing Sound Instead of Microphone Playback on Pavlovia (PsychoPy v2025.1.0)

Online experiments
1

Hi all,

I’ve created an online experiment using PsychoPy Builder v2025.1.0 and uploaded it to Pavlovia. The experiment includes a simple microphone check where participants record a short audio clip and then hear it played back immediately.

The issue is:
:backhand_index_pointing_right: Instead of hearing the recorded voice, I hear a buzzing/static noise during playback.
The microphone recording is saved correctly (I can download it and hear the correct voice recording from the server), so it seems the issue is with something else**.

Setup Details:

  • Created with PsychoPy Builder (no custom loop)
  • Microphone component: 5 seconds, saving in .wav format
  • Sound component: uses $mic.savedFile to play back the recording
  • Sound starts 1 seconds after routine begins (I tried adding a delay)
  • Playback issue happens in both Chrome and Firefox

What I’ve tried:

  • Switching from .wav to .flac format or default format
  • Adding a delay before the playback starts (e.g., 1s)
  • Confirmed that $mic.savedFile returns a valid file path
  • Running on different systems and browsers (buzzing still occurs)

Important notes:

  • The saved audio files play back correctly when downloaded manually.
  • The buzzing sound only happens during in-browser playback.

I’d love any advice or insights — is this a bug with the microphone or sound component in PsychoJS? Or is there something I’ve missed in the setup?

Thanks so much in advance!

2

This is another “the PsychoJS microphone works differently than the PsychoPy microphone” problem I think. It looks like you’re trying to make mic.savedFile into a sound.Sound object. The PsychoJS microphone doesn’t seem to have a savedFile property. Try mic.lastClip instead. That will be an AudioClip object rather than an actual audio file, but the online version of sound.Sound looks like it will accept an AudioClip object for playback.

1 Like
3

Thank you so very much @jonathan.kominsky That saved my experiment! :slight_smile: