If you are using an D/E range Samsung, and find that after following all recommended content and hardware guidelines, you are still seeing blackscreens across your bank of screens, please see the steps below to rule out a UI bug with this player type first.
Identifying the ID of your sync group
Access the network where you are having an issue with sync
Select the Network dropdown box and then select Sync Groups
On the left of the screen select the sync group that you are having the issue with
From the list of players that appears select any player from the sync group
Under the Content and Screen On/Off tab there option to the right to Download Config
This will download a JSON file.
Open the JSON file (a JSON formatter may help read the required information)
In the JSON file there line containing "sync_group_id" followed by a number string which is your sync group ID
If this ID is over 1000 a Trello card will need to be made and handed over to dev to have them manually change the Sync group ID to something under 1000.
Once this work has been actioned, the Support team will notify you, and this change will be applied to your players as part of their next successful content check.