I'm having a problem whenever I run the Thousand Maws of Toto-Rak. Every time I join the dungeon my game freezes and I eventually have to force close it. This doesn't happen with any other activity in the game. Here are my specs.

Intel Core i7-3630QM CPU @ 2.40GHZ
16 GB RAM
Windows 8.1, 64 bit

Any ideas on how to fix it?