Thanks for posting here in the Community.
Can you please provide us with more specific information about the issue you are experiencing? I have a few questions to better understand the behavior you are seeing:
1. When did this issue first start occurring?
2. Does this issue happen on a certain channel or does it occur on all channels?
3. Have you tried removing the channel, restarting your device from Settings>System>Power>System restart (If you do not see a Power submenu, skip to the next step), then once it loads up again, adding the channel back once more to see if that clears things up?
4. Are you using a Roku player or Roku TV?
With more detailed information, we will be able to assist you further.