My camera has recently had a firmware update and the quality of the image has deteriorated after the update. 

Specifically the images are much more grainy and any areas which are illuminated by lighting (ie street lights, house window lights) are much more luminous in the video, obscuring large areas which were previously visible

The two images below illustrate. The first is with the new firmware, the second is with the old firmware

I have checked my settings are still the same, video quality is 2k, HDR is off

Is it possible to roll back a firmware update, and if not could someone review the latest firmware as it has significantly effected image quality