Yeah some problem here (although I do use the 110V here at work where I have a variac on my desk),

The Dick Smith 12V 1A wouldn't cut it (didn't try Tandy though - I have worked in both places) and the player kept rebooting. The Jaycar MP3130 for $30 odd has worked flawlessly for me with 1 30G drive so far. It's a switchmode too so it's compact and light too.