Slider preview thumbnail not loading properly

I am currently completing the developpement of a Moodle plugin to serve HLS video from our streaming server which uses Kaltura CE. The plugin uses the Kaltura player.

Everything is working well except for one thing. When I load the page with the Kaltura player, I get a 404 on this thumbnail url:


If I remove the “vid_slices/100” part of the url, I can see the thumbnail.

I understand that this is called by the player for thumbnail preview on scrubbing. Also note that the poster image loads correctly, as well as any thumbnail I call using kWidget.getKalturaThumbUrl().

Right now I’ve been able to deactivate this feature by adding “‘scrubber.sliderPreview’: false” to the flashvars property on load. But I’d like to be able to use this feature, so I’m wondering why I am getting the 404 on this url and how to solve this. Is it a server config that needs to be adjusted?

Thanks for any help that could point me in the right direction.