Greetings from the Roku Community, @hokelbo2!
Thanks for letting us know about your issue with the YouTube channel; the brightness is changing by itself. Is this the only channel that you are having problems with?
If this is the only channel, we suggest contacting the channel partner since Roku's channel developer maintains channels.
We're hoping to get everything sorted out soon.
Thanks,
The Roku Community Team
John
Roku Community Moderator