Thanks for the post.
This is possibly a hardware related issue that is affecting your screen. Have you tried contacting your Roku TV manufacturer support yet to inquire further? I'd suggest starting there to see what options or suggestions they can provide. Each Roku TV manufacturer provides direct support for their products running the Roku OS.
For a list of Roku TV manufacturers contact information, visit our Support page here: Contacting Support for Your Roku TV
Please keep us posted what you find out.
Roku Community Moderator