Cool thanks Andrew.
To be honest the post processing volume was the standard one that came pre-built in the 3D Side Scroller template. I believe I might have zeroed out motion blur, which could be why I could see this happening. As motion blur would normally blur the background as the character moves around. Ill take a look through the post process volume settings tomorrow see if I can workout the direcr cause. I understand even if everything is turned off, the post processing volume still adds certain things?? Or was that changed?? Like motion blur was set to zero and off, but was still added until I manually zeroed it out.