I have a M2 Mini Pro with 32GB of memory, 2TB SSD and 10 Gb ethernet working as a file server with an OWC four disk Raid. I had a LG monitor attached and never had any issues. I have had a lightning power port full sized Apple Magic keyboard with the Touch ID button. No issues.
I upgraded a couple of weeks ago to a new nano screened Apple Studio Display. Also mini now has MacOS 15.2. It has started sleeping very hard and the only way to get screen access to type password is to power off the mini.
Just got off call to tech support on this issue. He suggests only touching the “return” key to awaken everything. I will try that tomorrow morning. I do have a new USB-C power slot Magic Keyboard if this process fails.
Other choice is, of course, to use a Lightning to USB-C cable and plug into either the mini, or in my case, the Studio Display. The other variable is MacOS 15.2 but my M1 Ultra Mac Studio with two Mac Studios directly attached and M4 Max MacBook Pro Max with the same MacOS do not have this issue.
Interesting advice about the return key. In the ASCII table I think the return key (CR) is one of a few keyboard keys in the zero (bit) column (000 1011[1]). ESC (001 1011j and all the character keys have at least one bit “on”. So it may be a physical issue with the way the keyboard operates.
This morning, the Lightning Magic key board did NOT awaken the sleeping M2 Pro mini by touching the return key. Powered off the keyboard and powered it back on. Siesta continued. Connected the keyboard with Lightning cable to the Studio Display. The snores continued.
So the two changes in the system are a new Studio Display and MacOS 15.2 is installed. Battery on keyboard was around 90% late yesterday.
Swapped Lightning Magic keyboard for new USB-C Magic Keyboard with a USB-C cable to the Studio Display. Still sleeping.
Removed USB-C cable and keyboard and plugged Lightning cable directly into M2 Mini and made sure USB-C keyboard was off. Turned on Lighning keyboard and hitting return and other keys did nothing.
Swapped cable out for the USB-C keyboard with the same results.
Connected Lightning keyboard and same cable to MacBook Pro and it works. Swapped out for the USB-C keyboard and cable and it works on laptop.
So both keyboards are operational hardwired to the MacBookPro M4 Max with 15.2 operating system.
So looks like either the Studio Display or the operating system on the M2 mini Pro could be the culprits. Will escalate with Apple tomorrow.
Office temp is 69 degrees all the time so that is not a variable and the Mini is cool to the touch.
On an Intel Mac I would suggest a PRAM reset but using the 4-key sequence at startup is not supported by Mx Macs. However, this article on reddit suggests there is a way to invoke this via terminal commands.
sudo nvram -c
Note: I do not have an Mx Mac and cannot test this–and things may have changed since the article was written. Perhaps others can chime in here on this tip.
Unplugged and replugged Studio Display power. Hit return key again and images displayed. One would initially think the Studio Display has an issue in “sleep” mode but powering up signals the CPU to wake up.
There is a way to reset NVRAM on Mx Macs but it could be risky. See the caveats in this article:
In brief Mx Macs do a check of NVRAM (and the equivalent of SMC) if they are powered off for more than 30 seconds. Resetting is more complicated and risky, with the loss of system settings.
IMHO not worth it for trying to solve a keyboard problem.
Suggest holding whichever key or spacebar or return for about 2 seconds. after going thru similar with my m2 mini and 15.2 i found that ’ slow keys’ had been somehow activated- but finally managed via system settings to keep that ’ option ’ turned off.
I was looking at the Studio Display and realized that I had just reused the USB-C video cable from the prior LG display. Swapped out and installed the Apple USB-C cable that came with the Studio Display and issue seems to be cured. Will see how this works going forward.