Hi @Coneyparleg,
Thanks for posting in the Roku Community!
We appreciate your effort to reach us regarding the black screen issue when streaming Dolby Vision with Disney Plus and Netflix and we would like to know how to identify and resolve any playback issues.
If the behavior continues, review the suggestions from our Support page for determining why Why is 4K Dolby Vision not working on my Roku streaming player? | Official Roku Support
If the steps provided by the Support page still aren't helping, please reply and we will be able to assist you further.
Best regards,
Mary
Mary F.
Roku Community Moderator