Hmmm. Flash is often the culprit as Scott noted.
Have you changed the browser or anything similar just before this started? I play on PC and have never run into this before but it sounds very graphics-related - which Flash is!
Another possibility is in the Game Settings. In the gameclient - select Game Setting from the menu and scroll down to Putting Grid and see if it shecked "on". I doubt it matters, but you can check "Pip Animation" as well.
During play, you can select "Options" from the Menu to do the same things.