Yo Kass answered Is this happening just on YouTube? Or other sites too?I would try the following things:Make sure your browser zoom is correct. You can press cmd-0 / ctrl-0 to reset it on most computers I believe. Depending on your mouse, the might be able to scroll through zoom levels too.To determine whether it's a YouTube problem or a browser problem, I'd try opening YouTube in another browser too. Firefox, IE, Safari, Chrome... There are plenty of options for double checking.Finally, I'd check out the YouTube support page on the topic of "zoom" at: support.google.com/youtube/search?q=zoomIf your question isn't answered in the FAQ's, then use the contact options to reach out to someone from YouTube as it could be a site bug.