The problem has resolved itself. It seems to have been caused by the readings from the joypad's triggers, that I've mapped to turning the camera, being stuck outside of the normal range.

After installing the recently release update, the view I usually play in -- the one where the camera is where the driver would be but with the car itself invisible -- is pointing backwards. All other views seem unaffected. Pressing R for rear view points the camera towards the front, but only for as long as the button is held down.

Does anybody know how to fix this?