Mouse Sensitivity Reverts to Default Each Time Game is Run

The in-game sensitivity appears to revert to default each time the game is run. This, however, is not reflected by the in-game sensitivity option, and subsequent changes to the in-game sensitivity do not appear to do much. Fiddling with the sensitivity and window size seem to eventually resolve the issue for the running game instance, but I have been unable to create a reproducible method of fixing it.

This appears to only affect KB/M controls, as controller input is very consistent.