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TypeError: Cannot read property 'readPixels' of undefined

I am trying to run my experiment online. It’s an audio discrimination task. It works perfectly on the Builder and on the Coder. But when I run the experiment online, I get different errors depending on the navigator I’m using.

With Chrome, I get:
Unfortunately we encountered an error:
** TypeError: Cannot read property ‘readPixels’ of undefined *
Try to run the experiment again. If the error persists, contact the experimenter.

With Safari, the page it loads but:
Keys don’t work and the sound does not work.

Here’s a link to my project’s files, I made it public: [] You can run my file English_Perception.psyexp on PsychoPy to see what’s supposed to appear when I run my experiment online.

Here’s a screenshot of the error message I’m getting on chrome:

I tried going into the console on chrome to see what the errors were but I think it’s a problem with the underlying script and I don’t know how to fix it

Please help! Thank you in advance.


Hi, I have been having the same problem. Were you able to resolve it?

Participants in the US are having the same problem with Chrome and from IExplorer they get stucked in loading the experiment… However, participants in Spain and I can run the experiment online without a problem.