I just picked up a new 14" MBP (10/16/16 model) and I'm having issues with my external SSD that I use for photo and video editing. This same drive has always worked flawlessly with my 2015 i7 MBP that I traded in. It is a WD My Passport SSD 1 TB model with max read speeds of around 1050 MB/s. When I plug it into my new MBP it sometimes takes forever to mount, and once it does mount it is extremely slow to read and write. It will also randomly eject itself. None of these problems happened on my older machine. Black Magic disk speed test can't even get it to test properly. Sometimes it works fine but most of the time it is stuttering when trying to do anything. I have racked my brain trying to figure out why this is happening. Unfortunately I no longer have access to my older intel model to test if it would work fine with it vs the Apple silicon. I've gone through multiple cables to make sure that wasn't the issue, including the original C-to-C cable. I've also checked that I have the latest firmware on the drive. I was so excited to do much faster photo/video work on this machine, but this external SSD problem is hampering my ability to do that. The last thing I'm going to try is to reformat the drive with my new machine, but first I have to move some files around. It is already formatted to APFS. Do you all have any suggestions? Or do any of you have similar issues reading and writing to external drives? I've read that some external drives just don't play well with Apple silicon, and I'm hoping that's not the case here.
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14" Macbook Pro M1 Pro having trouble with external SSD
- Thread starter ahaynes42
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I suggest contact Apple. Best is if you could take it plus the SSD to an Apple store, where they might see if it has any issue on other 14" MPBs, and on other Intel machines. If you don't have other drives or computers, it is hard to do a process of elimination.
The only issues I have had is reading from SD card slot (I have a base 14" MBP).
The only issues I have had is reading from SD card slot (I have a base 14" MBP).
Thank you for the suggestions so far. I have since run into more issues with my other SSD randomly ejecting too. I can't seem re-create the issue on a consistent basis. Sometimes the drives work fine, other times they slow to a crawl and randomly eject themselves. This happens through a Thunderbolt 3 hub, as well as when connected directly to the ports on the computer. I'm really hoping it's software related and not hardware related, so it can be fixed with an update.
If you wait until 14 days is past, your options are going to be limited.
Unless there are thousands of people with the same issue as you, don't count on any software update.
I am having similar problems with my SSD. It is ejecting randomly and sometimes it is slowing the computer to a halt. I have to physically disconnect it so that I can have some work done. It happened on Big Sur and now on Monterey as well.
Well, seeing Big Sur won't run on these 2021 MBPs, yours is likely a different issue.
OP's issue is using an SSD with a 2021 MBP.
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I just came across this thread on Apple's forums where others are reporting external SSD issues with MacOS Monterey specifically. Some have intel machines. But then I also found this thread that seems to go back to the problem starting with Big Sur. Not very hopeful for a quick fix now, as it should have already been fixed by now. At least these threads seem to confirm it's likely not an M1-specific problem. It seems to be happening with Intel machines too, starting with Big Sur and now Monterey.
As I remember correctly from reading various threads on the topic these occurrences with Ssd being ejected started off with Big Sur and continued with Monterey. At least that's the case with my computer.
I guess I was giving Apple too much credit when I assumed that the 12.1 update would fix this issue. Nope. I still have a perfectly fine 1 TB external SSD that works with every other computer except this one. And I'm really disappointed that the much anticipated 12.1 update did not fix the issue.
I ejected mine and I'm not using it waiting for a fix. In the meantime I bought a 1 TB external HDD and so far it's been without any problems
Do open a case with Apple. The more people that complain over a variety of different drives, the faster this might get sorted out.
Apple really hit the nail on the head with the CPU and GPU on these new devices, but their connectivity support (USB, SD Card, external monitors) has been quite downgrade from the Intel.
Really hoping all this needs is some software tweaks, although the M1 has been out for over a year now, and people still report USB transfer speeds on that are significantly slower compared to the Intel counterpart.
6 months later and still no fix in sight. The computer goes crazy when I plug in this drive, just constantly mounts and ejects. If it does end up mounting it's slow and buggy. Works perfectly fine on every other non-Apple Silicon computer I've tested it on. Ridiculous.
I noticed this with the Sandisk and Samsung T7 SSD I have on my M1 Max Mac Studio and M1 Macbook Pro 16, and I had to run some commands to fix this to disable disk sleep.
However, I have no problems with Thunderbolt 3 SSDs. I built my own Thunderbolt SSD storage by buying a NVME Thunderbolt 3 enclosure (OWC Envoy Express) and putting a Samsung EVO 970 Plus 2 TB SSD. It runs more reliability with no speed issues like USB-C SSD. While it’s more expensive, you don’t experience any slowdowns or the drive ejecting. The downside is, to use it on another computer, it needs to support Thunderbolt 3.
However, I have no problems with Thunderbolt 3 SSDs. I built my own Thunderbolt SSD storage by buying a NVME Thunderbolt 3 enclosure (OWC Envoy Express) and putting a Samsung EVO 970 Plus 2 TB SSD. It runs more reliability with no speed issues like USB-C SSD. While it’s more expensive, you don’t experience any slowdowns or the drive ejecting. The downside is, to use it on another computer, it needs to support Thunderbolt 3.