Online experiment TypeError: Cannot read property '0' of undefined

[Nahuel]

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Help: TypeError: Cannot read property '0' of undefined

Hello I am receiving the following error when I run my study on Pavlovia ( TypeError: Cannot read property ‘0’ of undefined). The study runs well on PsychoPy. On each trial, I present videos and I want my participants to type what they perceive. When I play it on Pavlovia I can only hear the words and not see the video and also I get the above error on the screen while the words are being played.