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swipod touch Author

Level 1

76 points

USB problem/Thunderbolt on Mac mini M4

(USB mouse & keyboard) intermittent connection problems through various adaptors & cords:

Connected to the Apple USB-C to USB Adapter through the front USB-C ports - ok there.

But, on the back Thunderbolt ports, using my OWC Thunderbolt-to-USB-C adapter cord connected with a USB-C female-to-USB-A female adapter with either the mouse or keyboard does not hold a strong connection, sometimes not at all.

3 back ports and they're relatively useless to me right now. Any suggestions to make this Thunderbolt work?

Mac mini, macOS 15.1

Posted on Nov 23, 2024 2:46 PM

Top-ranking reply

D.I. Johnson

Level 7

25,703 points

Posted on Nov 23, 2024 5:22 PM

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.

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27 replies

Jan 16, 2025 8:40 PM in response to swipod touch

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!!!

Jan 17, 2025 2:14 PM in response to swipod touch

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!

Jan 18, 2025 8:45 PM in response to azurmaraces199

When I have my wired Mac keyboard connected to the back and power up the Mac Mini, it doesn't work if it's connected to one of the back ports, but it worked perfectly fine in the front ports.

I never use sleep on my machines; it seems we are all having the same issue, but there may be a few causes. As some posted here, I hope it can be resolved with software as using the front ports is inconvenient.

Rdkam

Level 1

12 points

Jan 19, 2025 12:40 PM in response to swipod touch

I am experiencing issues with all the rear ports. I plugged a monitor in from the back but when I plugged in another peripheral the monitor connect became glitchy. Same thing occurred when monitor was connected thru HDMI. Plug in another C , then the HDMI connection glitched.

I saw an article on this:

https://apple.news/AaP7mE6IIRzie2zdDxFUdtw

v8242

Level 1

8 points

Jan 20, 2025 11:50 AM in response to swipod touch

Anyone able to get an answer from Apple support? This is a massive miss on apple's part not to test their USB compatible ports before shipping to the masses.

Had headaches with the m2 MacBook years ago out of the box. Thought things would be different this time but quality continues to slip.

Jan 21, 2025 11:23 AM in response to v8242

My guess would be a problem with the power supply of the rear USB / Thunderbolt ports, which would be a hardware problem hardly solveable with a software workaround.

And, no, in absolutely no way is keeping the Mac permanently out of sleep mode a viable solution.

hcsitas

Level 6

13,574 points

Jan 21, 2025 1:06 PM in response to uwsc11

This looks like an issue with both the quality of the cable and also length (because of Thunderbolt which is more sensitive to cable lengths than USB).

How long are the cables in the back? Have you tried 3 feet or shorter (1m or less)? Use Apple cables if possible.

Jan 21, 2025 3:42 PM in response to hcsitas

My cable is 12" long and works perfectly fine in the front but not the rear ports. It's an Apple production issue if everyone on here is having the same issue with the rear ports. I'm sure we're all using different cables and different devices but experiencing the same problem with the same ports, and we all are fine when we use the front ports

Jan 21, 2025 4:35 PM in response to swipod touch

Had the exact same problem.... now solved. The information herein might help others with troubleshooting.

I have an M4 Pro Mac mini and an Apple Studio Display. Have 2 Apple keyboards. One about 7 years old (Bluetooth) and another about 13 years old (Model A1243). Both have the numeric keypad. The older one has a USB-A connector.

I prefer the older Model A1243 just for the feel of the keys. But it would work intermittently when plugged directly into the Mac mini or the studio display (used Anker adapters). The front ports on the Mac mini worked best, but still were intermittent. Very frustrating.

Also have an OWC Thunderbolt-4 dock. Eventually plugged the dock into the Mac mini. This dock has a USB type-A port. This dock also comes with optional software for ejecting disks connected. But per OWC:

"When you install this app, a driver is also included for the dock’s high-power USB ports. The driver enables use of the Apple SuperDrive and USB Keyboard on these ports, and should enable them to charge 1st, 2nd, and 3rd generation iPads as well."

Installed the dock driver and plugged the old USB keyboard into the Type-A port of the dock. The keyboard works perfectly! I've been using it for a couple of weeks.

So.... I am wondering if the issue has something to do with the power (or voltage?) being provided through the new generation USC-C and/or Thunderbolt ports for old USB devices. Note that OWC dock has its own power supply.

Anyway, hope this info helps.