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I have a Mac Mini and some 4tb drives in Enclosures attached to the back, it disconnects
- Thread starter Crazytile
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How many drives do you have?
Are these 2.5" drives that rely on the Mini to supply USB "bus power"?
If so, have you considered using a POWERED USB hub?
Are these 2.5" drives that rely on the Mini to supply USB "bus power"?
If so, have you considered using a POWERED USB hub?
they do not have power on them. Should I get one with it or replace them? I do not think this is the issue. I read on somewhere there was a bug or something that is causing USB devices in rear to be disconnected.
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Can you clarify how many drives you have (2 or 3?), which type they are (HDD/SATA, SSD/SATA, or SSD/NVMe), and how they are connected (USB 3.x or USB 4/TBx)? Also, any correlation with sleep/waking from sleep, randomly while you are using, or left idle while you are away? Then which model/year of Mac Mini (2018/Intel, M1, M2, or M4)? Last, what version of macOS?
I have 2 SATA with NVME. Connected behind of Mac Mini 2025 TB ports. Sometimes when connected they just pop up nd say disconnect on the desktop icon and I never put them to sleep the mac mini. I actually put them to sleep when I am done for the day. I have 2025 Mac Mini M4 with 16 GB and 256GB drive with 2 external 4TB Samsung drives drives are 2024.
I am not quite following -- SATA and NVMe are types of interfaces -- a drive can either be SATA or NVMe. Then these can be put in an enclosure designed to connect to the host via USB 3.x or Thunderbolt 3/4/5/USB4. The most common configurations are USB 3.x - > SATA, USB 3.x -> NVMe, Thunderbolt 3 -> NVMe, and USB4 -> NVMe. Many enclosures can fall back from a higher/newer standard (e.g. Thunderbolt 3) to an older (e.g. USB 3.x) but these are still typically referred to the highest level they support (e.g. Thunderbolt 3).
Are you using a packaged product like the Samsung T7 or did you assemble an SSD / enclosure combination (e.g. a Samsung NVMe SSD in an Acasis enclosure)? If the former, can you share the specific model (e.g. Samsung 2TB T7 Portable)? If the latter, the model of enclosure and which model of SSD (e.g. Samsung 990 Pro NVMe SSD 2TB in an Acasis TBU405ProM1 enclosure)?
P.S.Note there is no Mac Mini 2025 (yet). The Mac Mini M4 is officially known as the Mac mini (2024). If Apple updates the Mac Mini line this fall, that would be the Mac mini (2025). However, even if you bought your Mini in 2025, it is referred to by the year the design was released (2024). I just mention for future reference as this may cause confusion if you are trying to debug a problem in the future -- a lot can change technically between models years (e.g. Mac mini (2023) and Mac mini (2024) are quite different). In any case we'll assume for now you have the latest Mac Mini and it is running Sequoia. Additionally, I will assume you have auto-updates on so running the latest version of Sequoia (15.4).
No problem -- then can you confirm the other questions -- are these packaged products (e.g. Samsung T7) or assembled units (e.g. your purchased a bare enclosure and SSD separately)? If the former, exactly which model and the latter, which components (e.g. Samsung 990 Pro NVMe SSD 2TB in a Plugable USB 3.1 Gen 2 enclosure)?
Note that there is a significant difference between USB 3.x and USB4. The latter is faster (better, etc) but seems more prone to problems like this under macOS.
P.S.Do you get disconnects on both drives or is it consistently just one of them? Also, are either of your drives connected to the middle USB-C/TB port on the back?
Could you define 'every now and then.' because I never experience dropouts with my mini m4pro, using two OWC enclosures, but I don't leave them on for days at a time. I did read someone had similar problems and it was power related, but they had 3 drives hooked up.
I'd still suggest a POWERED USB hub or dock.
(by "powered" I mean it comes with its own power supply that you plug into the wall outlet)
(by "powered" I mean it comes with its own power supply that you plug into the wall outlet)
I'm seeing the same issue from time to time. In my case, it's an iMac M4, and I'm seeing it across different drives. One is a Crucial X9, another is a Seagate portable HDD, one is a Samsung SATA SSD in a generic enclosure. All are plugged directly into the back of the machine, not into a hub. What also weird is that I'll come back to the machine after a while and see error messages about ejecting my drives before disconnecting -- but in the meantime they've re-mounted on their own. Seems very inconsistent and random too. I'll go several days with no issues, then find one or more drives randomly ejected overnight.
I use both OWC and Acasis controllers on two systems (mini Pro and Studio) using TB4/TB3, also Satechi and RayCue docks with drives using USB-C. None disconnect.
I have two Samsung NVMe SSD's in Sabrent USB C enclosures, and I experienced the same issue you were. It wasn't a power draw issue for me. After a lot of research, I found out I needed to update the firmware of the enclosures. Once I did that, I haven't had them disconnect since.
I did have to use a Windows machine to do the update, since the software to update the firmware doesn't run on Mac.
I did have to use a Windows machine to do the update, since the software to update the firmware doesn't run on Mac.
This is an ongoing error cascade regarding USB and the Mx processor range. There isn´t much you can do except buying a thunderbolt based case or a thunderbolt dock. Their USB implementation is rock solid compared to Apple.
Apples USB sfotware stack is very buggy and often non standard behaving. We have this, too, here, with many cases giving us only problems on Mx macs, but not in intel ones or any windows machine around.
Apples USB sfotware stack is very buggy and often non standard behaving. We have this, too, here, with many cases giving us only problems on Mx macs, but not in intel ones or any windows machine around.
OP, what MacOS version are you running ? while I agree the issue is probably power (or maybe overheating, some enclosures dissipate the heat better than others), it may also be an OS problem. I use 2 identical UPS's, both plugged into an M4 Pro Mac Mini (via USB-A -> USB-C adaptors) and since launch day, I'd get about 24-48 hours of connection from them, but after that time, one of them would disconnect. Come the next reboot, which was always for an OS update, it'd reconnect and the same would happen again. Since 15.4 was installed, they've been perfect, with no other changes made, or even the Mini, the cables or the UPS's even touched.
