Sadly, this has started happening to me. I have never had any issues with my Radeon since the game came out. I think this started happening with the last patch 2.35. I went to one A rank hunt and my FPS would drop and then the game would crash. When I teleport, everyone once in awhile my fps would drop and then I would be stuck on a loading screen. I would teleport sometimes and the game would crash to desktop.

Using i7 2700k
16 GB RAM
Windows 7 Pro 64 bit
Radeon R9 290x (Gigabyte Windforce)