I have this issue where a black box comes down from the top of the screen often. Some times it happens every few seconds several times in a row. I suspect that it is a notification box which is missing the text. But I have no idea why it is happening.
I tried disconnecting the HDMI device and it still happens.
I tried shutting down my AllShare server on the network, and it still happens.
I tried removing my Samsung account from the TV in case it was the cause, and it still happens.
I think the issue only started after I updated the firmware to version 111. ( I think it was the last digit of the version, I will check again when I get home to get the full version).
The issue happens while using HDMI.
Happens while using the YouTube 'SmartTV' 'app' (its really just a web page).
It even happens while the Smart Hub is up.
I still have to try resetting all settings on the TV and see if that helps.
I have not been able to find a way to revert the firmware, but I would try that for sure.
Video showing the issue: https://www.youtube.com/watch?v=am8Gl5MktAo
(This is recorded while my Raspberry Pi is connected doing an update.)
TV model: UN46F6300AFXZC
Specs: Samsung 46" 1080p 120Hz LED Smart TV