The M4 Mac Mini: USB-C Connectivity Problem

Since USB is a fairly robust technology, devices linked to it should normally continue to work for a very long period, independent of outside influences. Nevertheless, it appears that the M4 Mac mini’s USB-C connections are troublesome in a few instances.

According to several online posts that Apple Insider found, customers are experiencing identical issues. They often include USB-C-connected devices that either doesn’t connect at all or abruptly disconnects and becomes useless.

Going Down

The reports it found span a variety of time periods, starting with the late 2024 introduction of the M4 Mac mini.

On January 15, a commenter on Reddit explained that their USB-C keyboard “intermittently disconnects” and that they need to physically disconnect and reattach it in order for it to function again. The problem only appeared on the M4 Mac mini, and the identical keyboard was functioning properly on the user’s other Macs to rule out any hardware problems.

Similar problems with docks connected via USB 3 and a KVM switch not working after awakening the Mac mini were reported by other responders. Everything functioned properly after physically disconnecting and re-plugging.

Another said that since the freezes didn’t appear while utilizing the front ports, the problem was limited to the rear ports.

Power and Connectivity Issues

An end-of-December post also inquired about power problems with USB-C devices powered by the M4 Mac mini. Even while directly connected, a USB-C external hard drive was unplugged when a “I/O heavy” operation was carried out.

Others brought up their issues once more, stating that hubs were functioning elsewhere but not with the ports. Although it doesn’t appear to be exclusive to the back set, concerns were expressed over the power consumption of the connected devices and if the issue was with the front or rear USB.

A hub connection issue was also mentioned in a previous article from November. But in that case, the poster claimed that they were not depending on bus power but rather were using an external power source for the hub.

In that case, one responder said that in contrast to their M1 Mac mini, their M4 Mac mini’s USB-C devices did not instantly reconnect. Once more, in order for the gadgets to function, they needed to physically link them.

Additionally, the problem has been reported on the Apple Support Forum. According to a post from November 23, the back USB-C ports were essentially worthless because they wouldn’t function consistently with attached devices, but the front ports functioned flawlessly.
Others who experienced identical issues—hard drives that connected to USB-C at the front functioning but not mounting to the back—were also mentioned in the replies.

Users may find these signal dropouts unpleasant, and there are several possible causes

The identical issue was reported by a user on the Mac Resource forum, where it was prevalent. They found that a Logitech mouse plugged in straight worked, but the Apple Extended Keyboard didn’t operate around the back when connected through an adaptor.

In that instance, the front ports seemed to function properly.

Puzzling Problem

Because there are so many factors involved, diagnosing the problem is challenging. Apple may potentially release a software update to address this issue, as consumers have claimed that it occurs while their hardware is sleeping.

Outside of Apple, the majority of consumers could discover that they can perform many tests to ensure that they are not the source of the issue. It will be beneficial to check the cable for damage, particularly checking the ports for debris, and to use a known-to-be-reliable cable in the configuration.