4 ms·

This reminds me of two things I experienced when I added a Mac Mini (M2 Pro) to my setup. 1. When I connected my iPad Pro M1 to the Mac via a 10Gbps rated USB-

This reminds me of two things I experienced when I added a Mac Mini (M2 Pro) to my setup. 1. When I connected my iPad Pro M1 to the Mac via a 10Gbps rated USB-C/C cable, it only connected at USB 2.0 speeds (480Mbps). However, when I used a USB-C to USB-A adapter, then a USB-A to USB-C cable to my iPad, it connected at 10Gbps. My suspicion is that when it has the full USB-C wiring on both ends, it might try to establish a Thunderbolt 4 connection, fail, and just fall back to USB 2.0, rather than trying USB 3.x? 2. On a slightly unrelated note: I found the USB-A ports (or rather, their controller) to be really unstable when using a hub, everything works fine when connecting devices directly to the Mac, but with any of the hubs I tried, I saw USB devices becoming unresponsive or resetting over time. A similar setup worked fine on my Windows PC. The most unstable was a simple (i.e. 3 USB-A ports and Ethernet) USB-C hub which I tested with an adapter ("proper" one with VL160 chip); for fun I also tested it with an ungodly chain of almost every USB-C/A adapter I had on the USB-C/TB ports, where it worked fine. Having to do a bunch of troubleshooting to set up my USB peripherals on the Mac was a bit unexpected, at least the USB-C/TB ports seem to work well (other than that iPad weirdness), so I'm happy I went with the Pro model for the additional two ports. (Note: While I didn't really approach this too methodically, I believe I tried enough combinations of cabling and hubs to exclude a simple issue like a faulty cable.)

thrdbndndn 2y ago
For 2, I usually blame it on the hub; but it's hard to find, or even define what is a "proper hub". I genuinely don't know how they work (like, if I plug 4 external HDDs to a hub surely they have to split the bandwidth? Is there a limit?) and what spec they are supposed to follow to make they work 100 of 100 times across multiple OS. I have ones only work well on PC, and ones only work well on MacOS in all these years. I tried to purchase not-so-cheap ones but at the end of the day it's still a gamble everytime.
- winkelmann 2y ago
  Hubs are part of the USB spec I'm pretty sure. The hub's controller should also handle bandwidth bottlenecks. As for the hubs in point 2, I am actually using a chain of three USB hubs between my Mac Mini and some of my peripherals (4 hubs if you count an internal one), which so far has worked without issues; I think all three of them caused instability on the USB-A ports. Again, the ports work fine when only one peripheral is connected directly, I plugged in two disk enclosures that saturate 5 Gbit/s and didn't see any issues when reading from both simultaneously.
  - thrdbndndn 2y ago
    Most of issues I encounter with hubs are during plugging/removing a device from it. For example, I have at least 2 hubs that will lost all of their connected devices temporally if a new (externally powered) 3.5" HDD is connecting. They work fine after that. I assume it's related to their (poor) electric design than the information signal part.

thrdbndndn 2y ago

For 2, I usually blame it on the hub; but it's hard to find, or even define what is a "proper hub". I genuinely don't know how they work (like, if I plug 4 external HDDs to a hub surely they have to split the bandwidth? Is there a limit?) and what spec they are supposed to follow to make they work 100 of 100 times across multiple OS. I have ones only work well on PC, and ones only work well on MacOS in all these years. I tried to purchase not-so-cheap ones but at the end of the day it's still a gamble everytime.

winkelmann 2y ago
Hubs are part of the USB spec I'm pretty sure. The hub's controller should also handle bandwidth bottlenecks. As for the hubs in point 2, I am actually using a chain of three USB hubs between my Mac Mini and some of my peripherals (4 hubs if you count an internal one), which so far has worked without issues; I think all three of them caused instability on the USB-A ports. Again, the ports work fine when only one peripheral is connected directly, I plugged in two disk enclosures that saturate 5 Gbit/s and didn't see any issues when reading from both simultaneously.
- thrdbndndn 2y ago
  Most of issues I encounter with hubs are during plugging/removing a device from it. For example, I have at least 2 hubs that will lost all of their connected devices temporally if a new (externally powered) 3.5" HDD is connecting. They work fine after that. I assume it's related to their (poor) electric design than the information signal part.