Partsman-Chrome started doing this when the Flash update came out. Apparently Chrome updates automatically and the 10.1 version of Flash is causing some of what you are seeing. I used Chrome exclusively until it started doing this. I switched to Firefox and the problem went away.
Updating video drivers fixed the problem for many. Unfortunately, I can't update my laptop drivers so I'm staying with Firefox. If you're on a desktop PC you might try the driver update.
These threads go into greater detail. GL
http://wgt.com/forums/p/6345/39327.aspx#39327
http://wgt.com/forums/t/14997.aspx?PageIndex=2