Shboom,
Al is writing about the touch-screen 'buttons'.... no ordinary buttons.

I guess at the end a display(screen) replacement will be needed ??

Several times I played the PA1Xpro, but can't get used to the touch-screen. e.g. it is weird key-activation starts after 'releasing' the button.
Often wrong functions start, because of the tiny squares available for the buttons.

Do NEVER use contact cleaner in touch-screens !!