he SD card reader slot on the new 14 and 16-inch MacBook Pro models is not functioning as expected with some SD cards, according to multiple reports on the MacRumors forums.
In a long complaint thread, MacRumors readers have detailed the issues that they’re having with some SD cards, and there seems to be little consistency between reports and affected SD cards. Some SD cards crash and can’t be accessed, while some have unusually slow transfer speeds. MacRumors reader Wildct explains the issue:
Same issues with 14″ M1 Pro. Just seems to be super flakey and inconsistent. Half the time it’ll recognize the card successfully (though it takes anywhere from 30s to 1m) and half the time it’ll throw an error. These are all Sandisk Ultra cards, both XC and HC, that were formatted in my camera. I tried reformatting them w/ the MBP and that didn’t seem to make a difference. All my cards work as expected in my 3 other USB card readers.
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