Audio file not playing. Error: failed to load because no supported source was found.

pmandara

Hi all,

I am currently attempting to run my experiment online with JATOS but I keep coming across an error that I did not encounter when running the experiment normally with OpenSesame.

The experiment is a speech discrimination task, during which subjects have to hear 10 blocks containing 30 randomized recordings each (the same 30 recordings are played in all blocks but in different orders) and make a decision as to what word they heard by clicking two keys.

The specific structure is: an audio plays, a sketchpad item appears (displaying the two words subjects have to decide between), subjects click on their keyboard (within a certain amount of time or else the next recording will be played automatically), an empty sketchpad appears and so on.

A specific error has been continously occuring when running the experiment online, namely a particular audio file fails to play across all 10 blocks of my experiment. I accessed my Google chrome console and the following error is displayed any time that specific recording is supposed to be played:

uncaught (in promise) domexception: failed to load because no supported source was found.

I was wondering whether anyone knows how to fix this? And please let me know whether you need me to provide additional information to understand what's going on.

Thanks in advance!

kri

Hi pmandara,

I've never had this particular error before. It looks like the the browser can't load the file. Maybe it's a broken path? Can you share with us the part of your code where you load the files?

Best,

Kristian

pmandara

Hi Kristian,

Thanks for answering! Here's the part of the code (I believe) you asked for:

set volume 1
set stop_after 0
set sample "[geminate_type]_[ratio].wav"
set pitch 1
set pan 0
set fade_in 0
set duration 0
set description "Plays a sound file in .wav or .ogg format"

So basically I uploaded my 30 recordings in the file pool. Each of the recordings represents one of the 30 possible ways my two variables (i.e. 'geminate_type' and 'ratio') may combine and I named all the recordings to reflect each of these possible combinations (e.g. one recording is named 'plain_0.6' where 'plain' is a possible condition for the first variable, and '0.6' a possible condition for the second variable).

Then I created a sampler item and typed "[geminate_type]_[ratio]" to make sure that each of the recordings will play.

kri

Ah, I see it's not JavaScript. I guess this is OpenSesame's programming language (was it Python?). Unfortunately I'm not family with this one. Anyway in the browser it's JavaScript and and OSWeb translates to JavaScript. If it is possible, can you attach your JATOS study here? Then I can have a look on my JATOS server.

Best

Kristian

sebastiaan

Hi @pmandara,

This issue is probably related to OSWeb, which is the software that actually runs the experiment. JATOS is the server software that stores data, generates links, etc. (The difference is a bit subtle, I appreciate that.)

To narrow this issue down, could you:

• In OpenSesame, under Menu → Tools → OSWeb, check if there are any issues listed under 'Compatibility check'. If there are, then your experiment uses functionality that is not supported in OSWeb (see here).
• Make sure that the audio files are included in the file pool. (And not, for example, placed in the experiment folder as separate files.)
• Test whether the experiment runs with the 'Test experiment in external browser' option in OpenSesame.

Cheers!

Sebastiaan