Are you trying to load just a single Still and the single still won't load? Is there something that is loading into the channels on boot up (there is a Default Media Feature that lets you assign this.) if there is something in the channel first eject all the channels and then try again.
If that still does not work you will need to contact tech support and open a ticket.
https://support.rossvideo.com/hc/en-us
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Les O'Reilly
Director - Switcher Product Management
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