Welcome to the Roku Community, @shelliesmith19!
Thanks for stopping by and reporting the closed captioning issue you're currently experiencing on your Roku TV.
You can customize the closed captioning feature design by navigating to your Home screen. Scroll up or down to select Settings > Accessibility > Caption style. If Accessibility is not listed, select Captions.
- Adjust each style element. A preview appears with an example of the changes.
- Text – style (font) / edge effect / size / color / opacity
- Background – color / opacity
- Window – color / opacity
For reference and more information about this, you may visit this support article dedicated to this: How to enable closed captioning
Furthermore, please be informed that if you are having this issue on a specific standalone app, they have their own closed captioning feature and can only be changed or customized directly on their app.
We hope this helps!
Best regards,
Carly
Carly Y.
Roku Community Moderator