Hello,I saw this video
https://www.youtube.com/watch?v=CAG-pYuXdg0
and tried the same thing as on video,but without succes,even powered hub didnt help me,so I searched on internet and find,that problem is maybe in kernel and its config....I have latest update from booxtore,so my question is If someone have tried connect keyboard with initial firmware from factory and what was the result.