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Audio stimuli cut short during trials

OS: Win10
PsychoPy version: 3.1
Standard Standalone? (Y)
What are you trying to achieve?:

A transcription task with a free-form text response. Auditory signal manipulations are played prior to transcription, and these are randomized by Block via nested loops.

I have the entire experiment built and running, using both Builder and Code components – though, some audio stimuli are cut short while a condition progresses. This initially seemed random, though it appears now that truncated signals are always the items of relatively longer duration. Further, if one of the longer stimuli is randomly selected as the first item in a block, then only stimuli of longer duration appear to be cut short during the following trials in that block.

Might this be a buffering issue? Can I fix this using the backend? Any ideas on how to avoid auditory stimuli being cut short would be much appreciated!

Many thanks,

Ryan

As potential solutions, I have 1) Left the duration field within the sound object blank (believing that would allow each signal to run its course), 2) Extracted the duration of each item, included it within the spreadsheet as a variable: $Duration, and input that variable name into the duration field within the sound object, and 3) Specified the total duration within the sound object using a specific estimate that I know to be longer than any of the signals: 5.0 sec.

Signals are still being cut short. Any ideas?

Thanks!

It seems that Psychopy imposes a maximum duration on all auditory stimuli within a condition/loop based on the first item read in from a list. As a hack, I’ve managed to get around this by creating stimuli-lists with one silent item (of longer duration than my longest stimulus) that is always played first in each condition. I’ve written code to then randomize the presentation order of all stimuli that follow the silent item.

Not ideal, but it works – and my stimuli are no longer chopped off prematurely.

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I’m currently adding a much better audio backend (using the audio engine from Psychophysics Toolbox ported to Python). I’ll look at this carefully as part of that work, and might get you to test it out too :slight_smile: