I am having the same problem and this yellow flashy image interferences are really annoying! Occuring since the last big update some weeks ago (DCS 2.5.6.57949 Open Beta). Installed latest drivers 457.51 (GTX 1080Ti) and played with different MSAA/SS settings today but without getting a change.
I am flying WWII only, today I took off in MP (RAF662 server), the mission just started, only 2 fighters active (more to come with mission progess), no artefacts while flying patrol over channel until one AI fighter reached dover and was shot by flak, this time first flashes occured. Maybe it has something to do with that new big greyish flak clouds???
Anyway ..., can only say that this yellow flashes could drive you crazy and I am looking forward to a fix.