My TT40/400 is 11 months old. Until recently it has worked very well. The problem started after the recent major software update was downloaded. When I turn it on after a few moments it goes blank then the start up screen (blue/gray map of the world) appears. The menu options freeze and don't allow me to navigate and I can't do anything but turn it off and back on and I may get a successful restart that displays the map and the menu options work again, but a short period it crashes again. I deleted and reinstalled the maps, as it appeared the maps were failing to load into the unit's memory, just in case corrupted map files were causing the problem. When this did not resolve the problem I reset the unit to factory settings but that has not worked either. Just meant I've lost all my favorite settings, routes and places. Strangely today the unit still recorded trip statistics, even though the screen was blank (no map). However, the headset and i-Phone connected OK and were and working. This makes me think the issue is a software problem, not a hardware problem. I need help. Can anyone advise me how to get my Tom Tom 40/400 working again?