Several times every day YouTube shuts down some of their servers to update stuff. Be patient if YouTube is slow, stuck or mangled. Transmissions from YouTube to your computer are done in multiple tiny packets of data and flash at a time. That's why sometimes you may get any of these scenarios: bits and pieces of text/thumbnails in weird places; sluggish loading/buffering; the spinning circle going on forever; or the player being blank. This problem could fix itself within a few hours or by the next day. If your YouTube continues to behave slow, stuck or strange, it's very possible that your directories of "temporary internet files" and RAM (sometimes known as "cache") are close to the maximum and just cannot take anymore, the end result being any of the above scenarios or videos that: A) come to a complete freeze; B) start/stop/start/stop in a choppy way; or C) never even make it onto your screen. "Temporary internet files" are tiny bits of webpages that get permanently put on your hard-drive. They will remain forever on your computer, gradually plugging it up like hair stuck in a sink drain, until you finally get rid of them once and for all. Thus, exit out of YouTube, then clear your "cache" of all its "temporary internet files", "cookies" and "history". It is best if you shutdown and reboot afterwards. You'll be amazed at how "fresh" and "new" your YouTube will be.