Game locks up on Chat use

I've been having a problem with game performance since 7.7 hit. I'm running on a macbook pro that is only a few years old with a fine graphics card and 16 gb of ram. Haven't had any performance issues to date, but since I patched and booted the game yesterday I've been getting really bad hitching in game. It's hard to tell what kind of behaviour it's tied to, as it seems like just about anything can trigger it. My connection gets me about 60 ping steady and I can run the game at well over 60 fps, but every time I type in chat, the game locks up for between 3 and 5 seconds. On occasion it's happened when other people use the chat a lot in game as well. That's not the only time, but it's the only one I've been reliably able to reproduce. It doesn't seem to be tied to the graphics or visual settings as issue happens in the same manner at very high settings and at the lowest settings.

Should I just reinstall? Or is this something into which others have been running.