I have an NEX-6 and 3 64GB SD cards, 2 new Sony cards and one and older ScanDisc. While out on backpacking trips, I will be shooting, then get a message that there is "Not enough memory left on card" once with 75 photo's taken, just this last week 624 photos. That card was new, formated in the camera and it's first use. Has anyone else had issues with this? I contacted Sony and they told me to format the cards in the camera and re-initalize the camera itself to default.