Thanks for reaching out. Just to confirm, have you tried following these steps to manage caption settings: https://goo.gl/EgiF6U ? Let us know if that helps.
Appreciate the info. Please send a feedback report directly from YouTube with these steps: https://goo.gl/WdI0BK . While every individual report may not get a direct response, we do review everything and use the details to investigate and fix issues. Thanks!