Mac mini M4 screen go black randomly

This is an update to my earlier post. I have the same issue with an HDMI connection. Generally I get a blank screen once or twice a day. This happens with different HDMI cables and different monitors. I contacted Apple support and they suggested that I try running in Safe mode and see what happens. Switching to Safe seemed to work initially, but eventually the screen blanking occurred again, although less frequently. The second suggestion was to try a Lightning cable instead of the HDMI. This seems to work. I have not had the issue for 6 or 7 days now while not in Safe mode. I have updated to Sequoia 15.4 and tested the HDMI cable, again having the same blanking issue. I am sticking to the USB-C Lightning cable. I have a Mac Mini G4, 32Gb connected to a Dell U2720Q monitor.

Me again to relate my experiment with the alternative cable: a HDMI to DVI from macMini M4 to the Eizo monitor (which does not have a HDMI plug). No black screen at all !

Perhaps it could help to understand what's going on...

The macMini runs Sequoia 15.2

Update since the reboot. I've had one instance of black screening for a few seconds. I noticed it seemed to coincide with disk activity with my two USB external drives (slow).

Keeping watch... I suspect there's a timing/bandwidth issue with devices? I don't think it's a cable issue. I'm not using HDMI, FYI. USB-C (high speed). I'm using all three ports on the back - listed as USB 3.1 Bus by the System Report, none on the front - my hard drives are on a separate port from the monitor's port.

Me again after some time testing: no black screen anymore now.

I don't know what has fixed the problem. Because here are the changes in my hardware

- I have now another monitor. An Eizo with usb-c to hdmi cable. Instead of the old Eizo with hdmi to dvi cable

- I have also updated to last Sequoia version

Following up again - happened again once after update to 15.5 (24F74) build. I quietly count to 3 or 4 and it's back. It's really intermittent kind of thing. It was while during use. I might try making sure my drives are set not to sleep when not in use and see if that changes anything (just a hunch).

My old M! Mac Mini was doing this, and now my new Mac Mini M4 Pro is doing it. Randomly, some days are fine. Today it was a bit worse. I rebooted and as I was reading these posts it blanked about six times. I turned off my LG monitor and turned it back on and it hasn't blanked yet in a half hour. Will see.....

I forgot to mention that I switched HDMI cables and tried a USB-C cable that came with the LG monitor. Blanking continued. I am using HDMI right now, still hasn't blanked since I rebooted the LG monitor with the Mac on. Next time it does I'll try rebooting just the monitor again.

Here's the latest for me:

I opened a ticket with Apple support. They had me try various cables and that didn't fix my issue. I was a step away from a hardware replacement when I decided to flip the ports for my two monitors. The monitor with the issue is my "left" monitor that was connected to the Mac Mini HDMI port. I took the HDMI cables to my monitors out and flipped them. My "left" monitor is now connected to an external Thunderbolt hub. Since doing that about a week ago, I've see the issue maybe twice, which is WAY better than what was happening before. This leads me to believe that the issue is with the monitor and not the Mac Mini, the cable or the hub. Not critical since it's happening less, but still a little annoying.

My next logical step is to replace the left monitor....and if I'm replacing one, I'll probably need to replace both since the mismatch will trigger OCD.

I know this probably doesn't help all affected, but I'm seeing some positive results with this change.

Got an M4 Mac mini. Get horrible blackouts with AOC 4K 32" monitor, wasn't getting any on my older Dell 27" 4K monitor but now it's started doing it on this one too.

Have bought numerous certified HDMI cables, USBC>DP, nothing helps. Really frustrating.

I got an issue that was never presented before on my mac mini m4. After external booting i got stuck on loop trying to boot normally with external SSD unplugged. When it successfully boots it says (SOCD iboot panic error).

I was using an USB c display and after i unplugged the display the mac mini restarted. Is there any possibillity of motherboard failure?

The HDMI doesn't work anymore or rarely. Does anybody have a solution or should i take it for a repair?.

I'll add a "me too". Identical problem... screen goes black for a second or two then returns to normal. It's sporadic but happens every time I use it. Occurs most often when using Safari, but also at other times. Cannot find a correlation with any other activity. Running a dual monitor setup and it only happens to the "main"/#1 monitor.

M4 Mac Mini, 500GB SSD running Sequoia v15.5 (although the issue appeared as soon as I bought it running an earlier version) connected to two LG 27UN850 27" 4K UHD monitors, one by Thunderbolt, one by HDMI.

I've switched out the monitor positions, switched out which monitor is using which cable, replaced both cables, hard reboot, etc. No improvement. Issue continues. So it's not the monitors, not the cables.

Upgraded from an M1 Mac Mini - same dual monitor setup - never experienced this issue.

Apparently it's down to the M4 Mac Mini. Annoying but not the end of the world. Hopefully Apple will address this at some point.

@Brian Hartmann: Have more-or-less the same setup. However I've swapped monitor positions, swapped out HDMI and Thunderbolt cables, swapped out which monitor uses which cable to no avail. It's always the left ("main") monitor that blacks out.

Just a reference point. For me, that tells me it's not the monitor(s) nor the cable(s).

@Brian Hartmann, it sounds like the only difference between our setups is that you're driving your main/left monitor with a Thunderbolt cable connected to an external Thunderbolt hub?

I have tried both HDMI and Thunderbolt cables on both monitors with the same, periodic blackout results on the main/left monitor (never on the right one). However in my case the Thunderbolt cable is connected directly to the Mini.

Above my pay grade as to why a hub in the mix would change things, but I'm glad it's working for you. I guess I need to come up with a good excuse to add one now. 😉