I am facing black crush on my samsung s9+ image outputs are like highly decompressed pictures worst experience. AlsoThere is no physical harm occured on my device this error could be manufacturing defect or software related issue.
Samsung has not been said anything about this wide issue were most of the s series users are facing now. Now my s9+ amoled display provide worst quality media output even my realme c1 5000 rupee costed smarrphone shows 10 times better display quality .
samsung response will cost a lot of time and until lockdown oled replacement is only solution you could try the chat service of samsung but these apps are free and can be uninstalled anytime they won't harm your phone only help in checking once factory reset karlo clear cache of phone