Internal SD Card Reader Incompatibility Issues with Certain SD Cards After MacOS Update

After a new version of MacOS (likely Sequoia given the dates) the SD cards I used for my 3D printer weren't being picked up by the internal SD card reader of my MacBook (M2 Pro MB Pro) Upon some similar investigation I did today I found that some SD cards work while some didn't, At first I thought it were an issue with my MacBook, so I took it to a genius bar (June 21, 2024) and another MacBook from the store exhibited identical results . This was over half a year ago at this point and I'm quite disappointed that the issue is yet to be resolved.

Test Environment:

Tested with the inbuilt SD card read on my M2 Pro MB Pro along with a Sandisk SD card reader and a Anker SD card reader.

SD Cards (with specs, using MicroSD to SD adaptor for MicroSD cards):

• goodram 16GB SDHC/UHS-1/Speed Class 10
• SandDisk Ultra Plus 16GB SDHC/UHC-1/Speed Class 10
• SandDisk Extreme MicroSDXC (using correct adaptor) 128GB/UHS-3/V30/A2
• Sandisk MicroSD 2GB/ no specs listed
• Sandisk Extreme Plus MicroSDXC 32GB/UHS 3/V30/A1
• Sandisk Extreme SDXC 128GB/UHS-3/V30

Goodram 16GB SDHC/UHS-1/Speed Class 10

• This SD card came with my 3d printer and is required to be in FAT32 (MBR partition map) for my printer to read it
• It was readable through the port on my MacBook, but not anymore However it's readable through both attached dongles with FAT32
• Tried:
  • ExFAT with GUID map, readable on the dongles, not readable on the internal SD card port.
  • APFS with GUID, same results as above
  • Mac OS Extended (Journaled) with Apple Partition Map same results

Sandisk Extreme Plus MicroSDXC 32GB/UHS 3/V30/A1:

• This was used in my raspberry pi, and it was picked up with internal SD card reader and dongles
• It was also picked up by internal SD reader and dongles when formatted to FAT32 with MBR
• ExFat & APFS with GUID also worked

SandDisk Extreme MicroSDXC (using correct adaptor) 128GB/UHS-3/V30/A2:

This is the SD card from my Phone, since it's got sensitive data on it I opted not to test different file systems but it was picked up by both dongles and the internal reader when using ExFat and MBR.

SandDisk Ultra Plus 16GB SDHC/UHC-1/Speed Class 10

This is another SD card that i use for my 3D printer and other devices, it exhibited the same behaviour as the Goodram

Sandisk MicroSD 2GB/ no specs listed

• SD card readers can pick it up and it's formatted to FAT16/MBR
• When formatted to ExFat MBR it's also readable from all readers.

Sandisk Extreme SDXC 128GB/UHS-3/V30

• This is my SD card for my DSLR, it's formatted to ExFat with MBR, since it contains sensitive data I opted not to test different file systems on it. However it was readable from the internal SD card readers and the external ones.

Conclusions:

It would seem that the internal reader has become fussy as to the specific SD Card classes it's able to read UHS-3 whilst not reading UHS-1. Considering that the hardware doesn't seem faulty I would assume there's a software issue with the SD card reader. I hope my findings are useful to the engineers that see this.