USB problem/Thunderbolt on Mac mini M4

I’ve having the very same problem with my newly purchased base-model M4 Mac Mini. My old Apple Extended Wired USB Keyboard simply won’t be recognized, or intermittently stops working (same with my old LogiTech USB wired mouse).

i’ve tried plugging them in independently, and switching out the third-party adapter to an Apple made more than the results are exactly the same. Never, ever had any issues with this keyboard and mouse with any other Mac I’ve owned.

Lose the extra cabling and adapters at the mouse and keyboard port. The USB keyboard and mouse don't require anything but a simple USB-A to USB-C adapter to connect to the ports on the back of the Mac mini. They are simple and affordable @ about $10 a pair on Amazon.

They look like this:

In fact, if your keyboard has USB pass-through you only need a single connection to the Mac mini. You can daisy chain your mouse through the keyboard. Unless I'm misunderstanding something here.

Sounds like the problem is how well USB-C sockets hold plugged-in cables, in general – rather than anything to do with Thunderbolt. I believe in this regards, the Lightning connector was a bit better than USB-C – even though the Lightning connector is not nearly as capable as USB-C.

The rear-panel USB-C ports on the M4 Mac mini are multi-purpose ports that support

• Traditional USB (I'm guessing at up to 10 Gb/s)
• USB4 (up to 40 Gb/s)
• DisplayPort
• Thunderbolt 4 (up to 40 Gb/s)
• [M4 Pro chip models only] Thunderbolt 5 (up to 120 Gb/s)

They adapt to whatever is plugged into them.

The front-panel USB-C ports on the M4 Mac mini are single-purpose ports that support

• Traditional USB (up to 10 Gb/s)

You can think of the USB-C connector as being like the concept of a "Swiss Army knife", and the things that live on it as being like the "blades". Some Swiss Army knives have more blades than others; and some USB-C ports offer support for more types of things than others.

You're welcome.

To put it simply, the Thunderbolt ports on the Mac are a combination of high-speed data connection and power delivery, and it also carries compatibility with USB protocols. You can therefore use it to connect simple, less expensive USB devices to your Mac and the more expensive Thunderbolt specified storage, monitors, hubs and other devices. Killing two birds with one stone, as it were. That's why in descriptions, the ports are often labeled as Thunderbolt/USB. I agree that marketing could be better.

I have a related problem. I just migrated to the Mini M4 from a 2015 iMac, and my backup protocol involves old HDD/SSD disk enclosures with USB connectors.

These work fine when plugged into the front USB-C ports (with adapters where required).

The same disks fail to mount when plugged into the rear T-4 ports.

Am I doing something wrong, or just not understanding the interoperability?

All of the USB-C ports on a M4 Mac Mini or M4 Pro Mac mini - front or back - should support USB 3 devices.

The rear-panel USB-C ports are the only ones that also support USB4, DisplayPort, and Thunderbolt. So normally the issue would be that you tried to plug something into a front-panel port that needs a protocol only available in the back. (Like a display or display adapter; or a hub that has both HDMI and USB-A ports.)

If USB-C to USB-A adapters work

in the front, but not in the back, I’d suspect that some piece of equipment was not standards-conformant. I couldn’t say whether that would be the TB4 ports or the adapters, but if they are third-party adapters, you might want to try a different brand. I’m guessing that Apple tests interoperability a bit more than third-party adapter vendors might.

Thanks, Servant of Cats.

Alas, I have just one Thunderbolt-compatible peripheral – the case for my external SSD (which does the heavy lifting alongside the 256GB internal). Also, my problem is the reverse of what you have mentioned. The drives are working fine in the front (USB-only) panel ports, but not in the rear (USB++) ports.

Hi,

I have kind of the same problem. My external ssd mounted at the back of my Mac mini M4 works fine. All other ports do nothing. I received the mini from apple on Monday. I'm a bit stuck now.

The cables and such that I use all worked fine on my old iMac.

Same.

Using a short USC-C male to female cable as a passkey saver will not allow the hardware to work when plugged into the rear port (it is fine going directly in).

When I plug the same setup into the front, I have no issues. I don't really like burning the front port and I don't like putting these hardware units directly in as they've been damaged very easily I'm the past.

Hoping the Satechi M4 mini hub won't experience these issues once released - I'm sure they're currently doing the testing as the release is coming soon

I have the exact same issue on both my M4 Mac Minis. I am using an older wired Apple-branded Mac keyboard (with the numeric keypad), and a USB-C to USB-A dongle or cable always works in the front ports but not on the back ports.

I don't think it's the dongle; I think it's the keyboard. I connected a Logitech mouse using the same dongle to a port on the back, and it works 100% of the time...

Hmmm....

I can't wait for the Satechi M4 mini hub too!!!

After much trial and error, the USBC issue is definitely on the rear ports and happens during sleep. I've had constant disconnects of hard drives connected directly (I've tried 3 different drives), usb hubs (I've tried 3, the last one is powered). Plugged in the front, I've not had any problems. It manifests itself when the Mac mini goes into sleep mode. I get the message that my Time Machine drive was ejected incorrectly. Hopefully this is a software bug; not good!