Thanks for the bug report! I must admit I haven't seen this one before :D
What Graphics settings are you using? You can open up the options menu to see. I'd recommend lowering the settings down to Low to see if the problem goes away. You can also use the "advanced" tab to tweak individual settings to see if you can narrow down the one that causes it.
Let me know if that works! If you could also send me the log files, that would be useful. You can see how to do that on this post: