SD Card Reader SUPER Slow in 2021 M1Pro MBP 16"

I have the same problem on a 16" MBP with M1 Max. The reader is unreasonably slow compared to my USB 3.1 external reader. It takes a very long time to start transferring when files are dragged to a folder on the SSD (10-15 seconds for a transfer of 100 photos) and is slow in transferring the data. Occasionally, it just throws an error and gives up. I'm using Sandisk Extreme Pro UHS 3 32GB cards that otherwise have been reliable.

I was not expecting the reader to be quite as fast as my external reader but this seems like a fault to me. I have followed K Shaffer's advice and reported this to Apple. I also recommend that others do this: include as many facts as you can (eg actual times, number/size of files).

This is a real shame because a built-in card reader is one of the improvements in this (rather good) computer.

I think there is hope. It looks like they fixed some of the problem in macOS 12.1and I expect they will continue to improve it. Reporting the problem, and your specific SD card type, directly to Apple should help them improve things.

Report at https://www.apple.com/feedback/macbookpro.html as previously commented.

A disappointing start.

If Apple felt there were more than a very small number of MacBook Pro with a problem, they would have issued a recall (they have not).

That leaves the possibility of a sample defect (an issue with your sample of the product). To determine whether that is the case, you can make an Appointment at the Genius Bar at an Apple owned store for an evaluation, free. Apple Authorized Service Providers can also evaluate your MacBook Pro, but they may charge an evaluation fee.

I have found the same. My SD cards when plugged into a cheap dongle are better than the built in slot. I guess the no dongle days are NOT over.

Oh no, well I exchanged mine to the pro vs the max and updated to the new software and it now works fantastic

make sure you have the brand new update

I had same problems as most folks above. I just updated to IOS 12.2 and it is now working as I think it should. Good luck folks!

Hello Christian:

You could do yourself ~ & others who may just stop here, a big

favor: by sending [Product Feedback - MacBook Pro - Apple]

instead of just commenting to this peer-based discussion area.

https://www.apple.com/feedback/macbookpro.html

By doing so (& if they so choose) you may be contacted further

for input. ~ Consider the process; and it's relatively benign. It's

almost a Bug Report; only a hardware issue, that needs action.

"Please read Apple’s Unsolicited Idea Submission Policy

before you send us your feedback."

Take care & safe travels! ☺︎

Looks like it may well be related to the particular card.

When reporting the problem, I'm sure it would help Apple if people gave as much info as possible about the card they were using (manufacturer, size, speed, all the stuff that's printed on it).

Went to download photos from a Sandisk Extreme 90 MB/s 32 GB this morning and had all kinds of issues with my MBP 14 with the new Silicone...think it must be M1Pro? I downloaded to 3 computers. First was a Imac (2021 intel) no issues and the download took less than a minute. Then did the same on my 16" MBP (2020) via an external reader...less than a minute. Finally used the SD card slot in the MBP 14 and all **** broke loose. Computer didn't show the card unless i want into the disk utility. Couldn't download and couldn't eject because I was getting a 'volume couldn't eject because it's in use". As per the Apple tec I shut the laptop down, took out the card, reinstalled the OS (same to same 12.1 to 12.1). Turn the computer on and now it sees the card but tells me it will take 40 minutes to download. Couldn't eject the SD card so shut everything down again. Plugged in my external reader and the download took about 20 seconds.

Was on the phone with Apple support twice and bumped up to second tier twice and disconnected twice. Not sure it was Apple's fault but they had my phone # and I waited for a call back...nothing.

Next step was to take the card (This one was a Sandisk, 32 GB Pixtor @ 48 MB's) out of another camera and do the whole download/archive routine. In the card slot in the iMac, external reader for the MBP then on to the card slot on the MBP 14. Much more data on this card and each transfer took about 4 minutes. No issues on the MBP 14.

I could push this all out of my mind since the second card from another camera seemed to work fine on all the computers and no issues on the MBP 14. But one of the key reasons for buying this laptop was to be able to use it in the field and do downloads there instead of in my office. So what happens when this issue comes up again...when I'm out in the field doing a shoot?

Doesn't seem quite so random, but then...it does seem random. Apple initially said it wasn't a known problem. I tried to point them to this thread.

So, Apple, how about letting us know what's going on? Have to travel tomorrow but when I get back I may try to escalate this to tier 3 or higher...maybe a replacement computer would solve the problem but how do I know? Will push though.

Andrew

Hi Christian,

A quick test on Monterey 12.2 gives the same promising results as you saw. I used my same card that has some times worked, sometimes not and got the following results.

Copying in the Finder, two tries separated by eject/remove/reinsert, SanDisk 32GB Extreme Pro (UHS-1, speed class 3) gave:

3.25GB/100 files mixed CR3 RAW and video - 38 seconds

2.72GB/100 files CR3 RAW - 31 seconds

The card is rated at 95MB/s read speed so roughly a GB in 10.5 seconds. On that basis, the reader can't go much faster. I was also able to Quicklook files on the card in sensible times, this has totally failed in the past. So I'm optimistic but will reserve judgement because I got here with 12.1 too.

Just updated to 12.1 and did a test. Card didn't crash, but the transfer rate is still horrendously slow. With a USB-C dongle external reader, the performance is 3.6x faster than the on-board slot.

Same here. I have a SanDisk 32GB Extreme Pro card, which is UHS-I with 95MB/s I believe. And it's EXTREMELY slow and will crash in a minute. But with a 10 dollars external sd card reader I previously own, it works fine and reads smoothly. I think it's a serious problem, the user experience is pretty horrible.

I have this issue as well. Extremely annoying. There's no reason why I should have to upgrade my Sandisk extreme Pro UHS-I cards if they work perfectly for me.

When I use an external reader they work fine, the issue is only with the built in reader.

Ive submitted a bug report.

I've had this issue too since the first time I used the sd card reader. I have a MBP 14 M1Pro. At first I thought it was a problem with the sd card, but it kept happening with other sd cards.

I've called apple twice about it, and they just tell me that I need to go to the store or send the computer in so they can replace the reader. Kind of frustrating to be without a computer for that long. I asked if apple knew about the issue and if they know anything, and they couldnt comment on it.

Does anyone know if this is a software issue or hardware issue?

I think it's software. Specifically Finder. It has been a nightmare to work with since I started using a Mac 10 years ago. There was one period of time where the copy/paste didn't work. Just glitchy.

This SD card issue is hit or miss. Fast sometimes, slow most of the time. Surely it's a software issue.