My trusty 2720 started acting up on Sunday and even after a master reset the problem was still there. Turn on and go though boot-up and it prompts for screen calibration. That's obviously not normal. Pressing the screen as instructed gives a cross hair but it continues to ask for screen presses, seems stuck in a loop. As the unit is no longer supported by Garmin I decided I had nothing to lose by taking it apart to see if I could fix it myself. I set the GPS on a tea towel to stop it skidding about on the table and damaging itself. There are 7 screws in the back of the unit. With all the screws removed hinge the adjustable bracket back out of the way Gently split the unit open and this is what you see inside Carefully lift the antennae and little silver plate up and back out of the way There are three little screws holding the green circuit board in place and a further four around the edge of the electronics. With hindsight I didn't actually need to remove the circuit board, I could have just loosened the four screws around the side and lifted the innards all out. Be very careful not to damage the little wires and ribbons which link the various elements And clean the screen, rubber seal and the inside of the outer shell of the GPS. There was some dust and dirt around the seal and the screen some of it quite gritty. Set the innards back into the shell and be gentle with the antenna. All back together again and ready to be closed up. Tighten the srews in the shell as tightly as you can without damaging them My 2720 is now back working again so the spare 2610 I have can go back into it's box again. :) It's a very simple job to do yourself and may well save you the price of a costly repair.