A visitor who has opted out of marketing cookies loads a web page that contains an embedded YouTube video. While loading the page, CookieTractor automatically replaces YouTube's iframe domain youtube.com with youtube-nocookie.com. With this approach, no YouTube cookie is set when the page is loaded.

Try updating your browser or clear your browser's cache & cookies. You can also check whether your browser extensions that block ads are affecting video playback. As another option, try opening YouTube in an incognito window with all extensions disabled and check if the issue continues.