I bought my SanDisk 64GB C10 UHS1 30MB/s edition microSDXC Ultra a few weeks back...I know I've had it only for a short time, but still....nothing so far.
Also read an article dated ~march, where sandisk said that they know there was a problem that it had already been fixed - and that the problem was with 32 and 64GB mobile ultra cards.....so the newer ultra cards should be ok...
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