Extremely slow external SSD read and write speed after Ventura update - MacBook Pro 16 M1 Max

Same issue with my Mac Studio on Ventura 13.1 while connected to a USB 3.0 Orico 5 bay RAID. Painfully slow speeds. I ordered a USB A to C cable and I'll try that and see if it helps at all to to use the lightning port on the Mac vs the USB A port. But first I'll try the 13.2 update and see if that fixes it.

M1 Mac Mini 2020 running macOS Ventura 13.2.1 & i'm seeing the slow read and write speeds when using my external ssd drive that's a Samsung 980 Pro in my Acasis Thunderbolt enclosure.

I used to get over 2500MB/s Write and 2500MB/s Read when using Monterey.

I kept getting the update notification to Ventura, and thought sure why not.

Unfortunately, "updating" to Ventura throttled my write speeds down to 500MB/s and read speeds to 2000MB/s.

Going to try doing a clean install of Monterey this weekend and will update this thread.

racer2k1 wrote:

• Reformatted all drives using FAT, exFAT in both MBR and GPT schemes

Have you tried using a native format like APFS?

Larry Jordan documented this a couple weeks back. Checkout larryjordan dot com.

Ok, so Blackmagic Disk Speed Test is broken on Ventura. (I see reviews saying it broke on Monterey, but it works fine for me on 12.5.1 using the 2021 M1 Pro)

On Ventura 13.0.1, I manually timed a 100GB video file transfer on all my external SSD drives. This was done using the native MacOS file transfer. This isn't perfect as it is all sequential data, but it is big enough to get past any sort of cache or buffer the drives might have.

All SATA based drives transferred within about 100MBps of their top spec. So 400MBps+ read/write on the SanDisk Extreme and Samsung T5.

All NVMe based drives hit the USB 3.2 Gen 1x1 bottleneck like they do on Monterey. Samsung T7 hit 800-900MBps read/write. Kingston XS2000 hit 900-1000MBps read/write.

So, essentially, everything works using MacOS Ventura's native file copy. I backed up these numbers using AmorphousDiskMark 4.0 and they are all close enough to be considered a tie.

That being said, an app that uses it's own file copy, might not be working right on Ventura. I'm still trying to figure out if having any apps running or peripherals connected in causing a speed issue or why the drives heat up when connected, but not active.

Again, this is just for me. I'll try and get some tests up and running using a Mac Mini M1 and a drive that supports Thunderbolt 3 and USB 3.2 Gen 2x2 if I make it into the office next week.

So this seems to be a major issue for a probably a lot of people. I really hope Apple is going to take a look at this. Never have I ever spent so much money on a MacBook Pro ... I maxed everything out in order to not have any issues for years when it comes to video editing and now this. Do people working at Apple ever take a look at their own forum/Community section?

So I manually timed some transfers and the numbers were better than I expected. Not as good as I get on Windows with USB 3.2 Gen 2x2, or even USB 3.2 Gen 1x1 (which should be the same as the M1 Pro/Max), but far better that what BlackMagic Disk Speed Test was getting.

Still not finished testing, but I am pretty sure BlackMagic Disk Speed Test is broken on Ventura.

Will have more tomorrow.

I have the same issue on a 15" MBP running Catalina and my new 16" MBP running Ventura. I bought a brand new Crucial 2TB external SSD this weekend to back up another 2TB SSD. Fresh out of the box Black Magic measured it at around 650MB/s. After the backup using carbon copy cloner the new Crucial drive returns read/writes in the 35MB/s. The backup took almost 8 hours. I also have several Samsung 1 and 2 TB external SSDs. They're all returning read/writes in the 35MB/s range.

My old SSD-drives are running with good speed on my Macbook M1 Pro. However, a new Samsung T7 Shield is very slow when reading from it. I also have a Samsung X5 with Thunderbolt, and that one is still very fast.

Many of you claim that this issue started with Ventura. I got the new T7 disk when I was already on Ventura, hence I have no experience with that disk on old versions of macOS. I returned the T7 disk and is now looking for an alternative with Thunderbolt that will empty my bank account.

I use a orico 40gbps nvme enclosure and a usb 4 certified cable with a wd black hard drive. On my pc I get over 2500mb/s read and write on y macbook air m1 I get less then 500 mb/s very anoying. After nearly one year it is still not fixed. I wonder when apple will adress this problem finally

Same issue. My external ssd (kingston 2tb) suddenly got really hot and ejected it self. The write speed of the ssd gone down to 100mb/s instead of 1gb/s. This happened after I updated to 14.1.1. It worked fine at sonoma 14.0 tho.

Recently we received an M2 Max, 38c GPU, 32GB RAM macOS 13.1. Didn’t restore using backups. Installed all apps fresh. That’s a pain, but no speed issues.

The same issue with Sandisk Extreme SSD. But i just notice 1 thing: when i connect this ssd to my iPad Pro it is working lightning fast. No any pauses at all!

Apple! WTF?

Additional info for Apple: External SSDs are getting very hot while connected with no file transfer happening. Even if they are unmounted, they are hot with no activity.

Cannot duplicate on a non-Ventura machine.

i had one hour call with apple support. we came up with three solutions:

1) when u make a new user - the problem is gone, so the first solution is to migrate data from old user to the new user

2) THE EASIEST solution is: go to settings - general - login items - and if you have app called "open" try to disable it and restart your mac - then try to plug in your hdd or ssd or sdcard if you see any difference (i tried this one)

3) when in that settings - click (i) info button near the "open" app and it will show a folder with it - backup it and then delete it - it just custom settings for some apps - could help too

in my case it worked - i can finally see previews of my raw files and its loading!

try it and let me know please