Touch Screen starts clicking on its own

Hi, I bought a used nintendo 3ds xl and the touch screen starts clicking by itself. The first time I switch on the console, it works without any problems, but if I switch it off and on again, the touch screen starts clicking by itself.

Should I try opening the console and cleaning it?

If I have to change the touch, is it just the touch or do I also have to change the LCD?

EDIT:
I've just opened the console and done some cleaning, the touch is quite scratched, could that be it?