Most video websites don't use Adobe Flash Player anymore, instead opting to use the built-in HTML5 video features on modern browsers. I would assume that Amazon has done the same, but I don't have access to Prime so I can't test. Assuming this is actually an issue with the Adobe Flash Player, you should check out the following pages to see if something from there helps you: *[[Why do I have to click to activate plugins?]] *[[The Flash plugin is blocked on some sites by default]] *[[Adobe Flash protected mode in Firefox]] However, it sounds more likely to me that you are having an issue with the DRM feature in Firefox. The [[Watch DRM content on Firefox]] talks all about the feature, what it does and how to block it (to enable it, which you will want to do, just do the opposite). Although, I think your specific issue could be that you are running Mac OSX 10.5, which is more than a decade old and doesn't appear to fully support DRM playback. Hope this helps.