Hi! My Surface Pro4 is having problem - there is a horizontal line where the pen loses its accuracy (the problematic line is located at the same height as the USB input). You can see the problematic line at the screen shot below. I use OneNote and DrawBoardPDF, and the problem is happening both, in the same place. If I draw with my finger the problem is the same... it seems like a screen problem, perhaps hardware, rather than a pen problem... how do deal with it?