I regularly flip back and forth between iPhone 4S and my Note. Hadn't used my Note in about 3 weeks and decided to switch over. No new apps and was working fine when retired 3 weeks ago. Plugged it in last night (not on) and charged overnight. Pulled it out of the charger this morning, took the back off, pulled the battery, installed my SIM, put it all back together and pressed the Start button. Got the familiar buzz then start-up screen, seemed to boot up fine but once I got to the home screen for about 3 seconds, the phone shut off and rebooted again. At this point it was an endless cycle, at least 3 times before I pulled the battery. Pulled the battery, took the SIM out, put it all back together and tried to restart. Nothing. Completely dead. Put it in the charger and all i get is a buzz like on start-up about every 3 seconds....continuously. Took it out of the charger and tried every combination of hard buttons and soft buttons to get something/anything to happen. Nothing. Fired up Kies on my laptop, updated to the latest version (don't use it that much) then plugged in the Note. Nothing. Well, I do get the same buzz every 3 seconds as I did in the charging dock but that's it. The battery was completely healthy 3 weeks ago giving me at least 16 hours per day between charges. I have again pulled the battery and will let it sit for a couple of hours but I am stumped. Any ideas?