Randomly going down to exactly 30 fps for no apparent reason

So, this started happening about 2 weeks ago. I don't know the exact time because at the time I thought it was just one of my mods.

Anyways, what happens is that sometimes the fps will go down to 30 fps exactly for no apparent reason. This seems to happen most often when something appears onto the screen suddenly such as when you examine another person, open the crafting tab, when monsters spawn in the forge and sometimes for absolutely no reason at all. None of these I could reliably reproduce though. This will also happen in the main menu out of the game as well.

Some other people seem to be having the same problem in which the fps drops down to exactly 30 for no reason. (I'm Mikro Maniac in this thread)

http://steamcommunity.com/app/322330/discussions/0/14 88866813759689839/

EDIT-- This has been happening in DS as well.

DxDiag.txt