This could be more then the same problem, one of you found a different card worked, what about the other guys?
Question: Are you guys all using a plug in power supply (power supply in cigar lighter)?
If so it could very well be a power supply that doesn't fit snugly enough and vibrates in and out of contact. Try wrapping some tape around the Power supply till it fits tightly, also try a new power supply if that doesn't work. They are low priced on Amazon and you should have a spare anyway, also don't buy a cheap one, get a name brand one like "Anker" for instance.