Delay in presenting audio stimuli

Hello,

I’ve designed an experiment where there is 2 lists of 12 video stimuli, one of the stimuli list being always followed by an audio stimuli (which is constant).

My problem is that the audio stimuli, which is set to be “presented immediately after the participant response”, is always being presented with a delay (between half a second and a couple second…). This problem makes the experiment invalid.

PS: the video stimulus list has also a problem, whic is that, after a few trials, the videos no longer play on screen, but in a separate window titled “activemovie window”. I’ve read that it may be a problem of codec compatibility. Could you confirm me this point?

Best regards

Can you tell me what settings are selected under the Stimulus tab > Settings> Presentation Options for your movie event? Also, what operating system your using (XP, Windows 7, Windows 8)?

I’m using Windows XP on a laptop with the following characteristics:

1.66gHz core duo
Graphic card Geforce 7300 with 256 Mb
2GB DDR2 Ram memory.

the settings of presentation are “allow movie to continue playing until it ends on its own”

I’ve tried running the experiment in smaller parts (making each block a single new experiment), no use, neither for the video issue nor for the sound issue.

I’ve tried running it on a more powerful computer (a desktop PC bought this year) no use with the sound issue. With the video issue, after a while, the video are not presented anymore (around the time the other computer should have popped up the activemovie window). Instead, i get this errors (see the PNG file)

I’ve tried to find where in the setting is the problem, but I can’t find it.

I’ve joined one of the experimental package, since you’ll ask for it anytime soon.

Thanks a lot for your help

problem superlab.PNG

IB.zip (5.02 MB)

Change “Allow movie to continue playing until it ends on its own” to “Wait for movie to end before ending: trial”. Use this setting for both of your movie stimulus lists.

Using “Allow movie to continue playing until it ends on its own” should only be used when two movies must play simultaneously. I do understand that the wording can be a little confusing.

thanks a lot for the speed of your solution.

it seems the video issue is now solved.

But the sound issue (i.e. a delay of a couple of seconds that shouldn’t be there) remains and still makes the experiment invalid.

for your information, the sound file starts with a silence period of 250ms. But the sound is still presented with a delay of a couple of seconds.

best regards,

Does someone have an idea about the delay of the sound stimuli? i’ve double checked every parameters (or so it seems) and wasn’t able to find the origin of the delay…

In the movie events, go to the Input tab and select “After any response from the participant” and be sure to un-check the time limit of 5000 ms. This will fix the delay your having.

It is working now indeed. Thanks for the quality of the support.

There is a new delay problem with the sound.

in one of the task, the subject has to press 2 button, and the sound have to be presented after the first press, whichever button it is.

after a few experiments, it looks like the sound is presented after the second press, even tough the correct response is set to be “one or more of the following” and the two button in question checked.

best regards

Are you using feedback within these events?