You Tube videos not playing?

Recently I have been having A LOT of trouble with videos at You Tube. They load incredibly slow and as a result the video won't playback right. It keeps stopping with the little spinner icon on it, and when it starts again it just keeps stopping again. The same pattern over and over. I have the latest updated version of Adobe flash player on my PC and I am virus free, so I have no idea what could be causing this. Any ideas?