Bought the wife a refurbed 4G nano. She charged it on our Mac, filled it up with all her music. We went on a trip and plugged it into our Belkin FM transmitter/charger that we bought for her old 2G nano. The screen display read "incompatable charging device" so we unplugged it and she attempted to just listen using earbuds instead. She got about 3 seconds of music and the screen and sound went dead. Tried several resets as described in troubleshooting docs and got no response. An hour later I turned it on and briefly got a screen saying "plug into power source" before the screen went black again. She had not brought her charging cord with her, so we borrowed a incar charger for an ipod touch, 3 hours and nothing but a blank screen. When we got home, we plugged it into the computer and the screen came on instantly and charged for about 3 hours, and everything seems fine. Anyone had any similar problems?