Check->uncheck Legasy (A7) mode - different render results

[Bormax]

Hi
While I was checking difference between different materials mode (Legasy (A7) mode and new GGX) I've noticed this bug.
To get attached pictures I did this order of actions:
Render,
 -> check Legasy (A7) mode -> uncheck Legasy (A7) mode -> Render,
again check Legasy (A7) mode -> uncheck Legasy (A7) mode -> Render,
and so on...
All settings are the same in all cases, but results on renders are so different, and they do not look correct - some strange stains of light appear in different places and overall lightness is different also.

Materials are simple light gray on the walls, boxes and sphere, darker gray on the floor.
Lighting - corona sun + corona sky.
PT+UHD Cache

On gif-file the differnce is more clear

[Ondra]

looks like a caching problem, can you upload me this specific file?

[Bormax]

looks like a caching problem, can you upload me this specific file?

Sure

[Bormax]

Thanks for your reply, Ondra! The probmlem was, as you said, with caching - UHD precision was set to 0.1 (do not remember that I changed it...). I set it to defoult 1.0 and everything works well.
Thanks!

[Ondra]

ok, no problem here then