Audio cut off at the start

shaza

OpenSesame version

v4.0.24

Operating system

Windows 10/11

Backend

Pygame (legacy)

Expected behavior

Target trials should play audio lasting about 2-4 seconds.

Actual behavior (what goes wrong)

Target trial audio starts "late", i.e. the first syllable sometimes gets cut off. The rest of the audio is fine. Can't see anyone else in the forum facing this problem, so it might be a unique issue? Can't seem to solve it though :(

For context, I'm playing audio stimuli back to back during my experiment. I'm using opencv to simultaneously play a video while the audio is playing.

What did you try already?

Added 300ms of silence at the start of the audio file as I thought it might be a loading issue so it needs time. The "lag" still happens.

Not sure if this is still related to stimulus prep? It tells me the file pool is larger than usual so I created a separate <__loop__> folder in the experiment folder (as mentioned in a thread I saw on the forum) but the message still shows.

Also not sure if related, but the practice block with fewer trials did not seem to have this problem. Previously, I tried a pilot version which had a different set of audio and fewer trials, and also did not seem to face this issue.

Not sure if attaching my experiment would be of help, but in case it does, here it is:

draft_20250813-fulldraft.osexp

You can find the target trial blocks after the practice blocks.

Thank you :)

cvanbuck

Hi @shaza

Thanks for sharing your file. I’m not sure what’s happening, but I’ll do my best to help you troubleshoot.

I noticed the file pool is empty (probably just to keep the upload light), but all your audio files are in .wav format, which is good. It’s worth double-checking that they all use the same sampling rate/bit depth and channel setup (e.g. all stereo), since inconsistencies can sometimes cause issues too.

Since the issue didn’t appear with fewer trials, you might also try splitting the experimental block into smaller parts. And to narrow things down, you could run the experiment once without the video to see if the problem persists; this would help check whether the video is interfering with audio timing.

Let us know how it goes,

Claire