I understand you would like to disable keyboard sound on your tablet.
Don't worry I'll try to help you out.
Did you make any changes to your tablet?
As you mentioned you are unable to boot into your tablet and after the tablet got updated.
Try the steps recommended below.
Slide down the quick settings menu.
Select Settings (gear icon) then choose User Profile & tap Predefined Profiles.
There you will see keyboard sign, tap on the icon.
A general page will display.
In there you will get dial-pad, touch, dialog box (uncheck this) & vibrate on touch (uncheck this too).
Tap the "Back" key on the ActionBar (top) or Navigation Bar (bottom) till you see the main screen and you're done.
If the issue persists, please try restoring the tablet to factory settings and check if it helps.
Refer this article to know more information about restoring the tablet back to factory settings.
Let me know if this Helps.
Have a wonderful day ahead! 🙂
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