Graphics options reset

Every other time I load the game the graphical options reset, or at least the dynamic reflection, and all settings under the preset subheading. I havent changed anything in the user directory nor have I changed my steam username or anything else. It only appears to be those settings as all others are fine. Additionally the game acts as if I have cleared the cache by reloading all textures slowly. Its not a massive problem, but very inconvenient.