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That sort of problem is reported for this keyboard model a fair number of times.
Replacing the display module inside the keyboard is the usual remedy.
The question is, whether the keyboard is still under warranty? if it were, then repair by a nearby Yamaha facility, free under warranty terms, would be ideal as a treatment for the problem.
Is your keyboard less than one year old?
If 'yes', then
What is your local zip code, please?
If you have electronics skills to replace the display module, and if the keyboard is out of warranty, then Syntaur offers a replacement display module:
If you need more info, want to let me know your local zip code, or have any comments, use Reply To Expert to respond.
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