Dear @David,
Thank you for posting your question in the Microsoft Q&A forum.
We apologize for any inconvenience you may encounter when using our services/ products. Based on your description, kindly try this:
Turn "Change brightness automatically when lighting changes" Off.
I sincerely hope you understand that the initial steps I suggested may not have completely fixed the issue, as there may still be underlying causes that have not yet been identified. I am here to work closely with you, troubleshoot effectively, and explore every possible solution to ensure the best possible outcome.
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