While working on some personal project, i encounter strange behaviour of hd cache, which i cannot resolve on my own. Its strange blobs of light. Each time it appears in different places and it doesn't goes awway with bigger amount of passes. I tried many things with little success. The only thing that helps somehow is lowering precomp steps of hd cache to 0,1 but whole image becomes grainy.
Ofcourse, i could render image with pt+pt and forget it, but i'd like to understand what causes such behaviour. Btw, i don't know if it's related to this problem, but hd success rate is unusually low in this scene - 50-60.
Attached gifs is not animation, its one frame rendered 10 times in a row.
edit: animated gifs seems not working here. Where i could upload them?