I've got a nice 2100 thats been kind of borked up since I got it.  The unit powers on and brings you to the screen calibration screen.  The screen responds to the touch of the stylus, but will never complete the calibration.  It'll just look back to the first point and keep going indefinitely.  I can bypass the sceen cal and all the old owner info is there, but the screen doesn't respond to ANY input at all.  Not even misaligned.  Physically the screen is in VERY good condition, and I've cleaned around the edges to try and remove any gunk that may be irritating the calibration.  Anyone had an issue like this before?  Is it solvable without replacing the screen?