I didn't find the problem until I noticed my SD cards were coming apart, the top left corner came loose. Some old and some new maps. Once when I tried to remove the card from the recessed slot, I saw that the top left corner lifted up, but the back of the SD card was still pressed firmly against the rubber base of the recessed slot. Then I check other slots and they all do the same thing. I found that the rubber base had been pressed into place, causing the slots to shrink a bit. As it wasn't under warranty I couldn't return it, I cut the outside edges of the rubber base (top and bottom) with an Exacto knife and the problem was gone, but then the insides fell out when I opened the case, the problem to forget. . I'm a professional photographer and I have a dozen SD cards for my 3 cameras, four of my SD cards are unusable and the other two showed little separation. I can't use cards for fear they will get stuck in the camera slots.
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