2018 Mac Mini - monitor problems

Not as helpful as you think. Some of us have tried ALL the ports, different adapters, different cables. First thing I would do in any case. I even had LG send me an extra set of cables just to make sure the first set wasn't defective. The problem lies mainly with Apple.

I am not quite as fancy as the rest here. Just a plain HDMI cable to the monitor. Works for weeks out of the HDMI port. Then when I go to log in with the monitor on - nothing. I had a USBC hub with a HDMI port on it. Plug it in and it works. Always works with the adaptor. Erratically with the HDMI port. So what is it?

Thanks....I'm just planning on using one monitor from USB C to DisplayPort . I would like to use this USB C (Thunderbolt 3) to DisplayPort cable https://www.amazon.com/DisplayPort-uni-Thunderbolt-Compatible-Pixelbook/dp/B07CL31FR6/ref=pd_sim_147_2/140-7066432-1830229?_encoding=UTF8&pd_rd_i=B075V27G2R&pd_rd_r=55500d71-4d9b-11e9-ab61-797b93d62bc4&pd_rd_w=8THk8&pd_rd_wg=FYKU9&pf_rd_p=90485860-83e9-4fd9-b838-b28a9b7fda30&pf_rd_r=68FCMF1PNPA0SS96C20A&refRID=68FCMF1PNPA0SS96C20A&th=1 and this LG monitor https://www.amazon.com/LG-24UD58-B-24-Inch-Monitor-FreeSync/dp/B01LPNKFK0 Should this work fine since 10.14.5 was released?

I have a Mac Mini late 2018 with the i7. It's hooked up via thunderbolt to a GPU in a Sonnet Breakaway box and a bunch of drives in a Thunder Bay enclosure, also via thunderbolt.

When I first got the computer, it was having occasional failures to connect to the Drives after restart, but more recently it's the eGPU that doesn't start up when the Mac Mini does.

Another problem I've had is the computer spontaneously shutting down every so often, most recently while I was reading something in a browser window.

In my many hours of conversations with various levels of tech support, I've found that Apple takes no responsibility for any of these problems and claims ignorance of any known issues.

However, on speaking with peripherals manufacturers and others, there seems to be a strong suspicion that it's something to do with the Mac Mini's T2 security chip.

The fix for the eGPU or Drives not connecting on startup is always to shut down the computer then unplug peripherals for 10 seconds then plug them back in and restart all together.

I just got off the phone with Apple re: spontaneous shutdown, and he had no idea how to fix it. He had me reset the PRam (unplug unit for 10 seconds then plug in and startup). Then he had me run disk first aid on Macintosh HD and then restart, after which he said that should solve it, but if it doesn't, I'd need to reinstall MacOS. That's all well and fine except for the fact that I've already done all of those things and yet the problems persist.

Hopefully Apple can fix these T2-suspected issues in future OS updates. Fingers crossed.

Does anyone knows a true solution that's available now?

Just to let you know, unplugging your mini resets the SMC, not the PRAM. The PRAM is reset by holding down the cmd and option keys along with P and R during start up. This explains the PRAM reset https://support.apple.com/en-us/HT204063 and this explains the SMC reset https://support.apple.com/en-us/HT201295

I want to purchase the mini instead of the new iMac since the mini has up to 10Gb Ethernet which will make it future proof. The new iMac still has only has 1Gb Ethernet. I'm guessing that in about 3-5 years we'll have at least 5Gb available to the desktop.

I know that most folks here are having monitor issues. I'll ask again, but with the recent OS update, if I connect one LG UD monitor from the mini using USB C to DisplayPort, will this work properly now? Also, someone mentioned the periodic switching of audio from USB to internal speaker for five seconds. That would be a deal-breaker for me. Are others experiencing this also?

> Even noticed some flickering on the screen, that's rare, it has got my attention.

Now that you mention it, after the 10.14.5 update on the i5 Mac mini, I also noticed some screen flickering at the login screen. The LCD monitor is a CMV CT-934D 19". I haven't noticed any flickering after logging in.

I haven't done the update on the i7 Mac mini yet (currently in the middle of a two day long 4TB Time Machine hard disk transfer to a bigger disk) but that one has a BENQ G2420HDBL 24" LCD also using a USB-C > VGA adapter.

I don't think the brand of LCD has an affect. The failure to wake problem is brand agnostic.

@FortranDino I'm guessing it's an i7?

I installed TG Pro on my i7 and totally overrode the SMC fan control which seemed far too slow to respond to increasing temperatures (mainly CPU). Before installing TG Pro the temperatures would hit 100C (the silicon max) before the fan rpms increased. Now I have the fan at 30% (of 4400 rpms) all the time, 35% above 45C, 50% above 50C, 55% above 55C, 60% above 60C, 70% above 65C, 90% above 70C and 100% above 75C. I haven't had a thermal "sleep" since.

My wife's 2018 i5 doesn't seem to have the same issue - ie it has never had a thermal "sleep".

Yes. It is a mini i7 2018

yes, the go to sleep auto shutdowns are occurring after 2.5 hours of editing on a very large word file.

perhaps this is really taxing the cpu?

i will try to install to pro and play with higher fan settings.

‘I will report back in a day or so if more fan means no auto shutdowns.

I was unaware that this issue existed until the 10.14.5 update rolled out. It was after that version installed I started to see my HDMI connected NEC display disconnect near the end of boot randomly. Looks like it took a long time for Apple to respond to the initial problem, and then they did so with an incomplete fix with possible regression testing issues, bad marks all around. And one user reports the next beta didn't help him. In the future I will be doing a full backup before allowing Apple to push a new OS version onto my mini, something I should have been doing all along.

Short update: My new mini arrived today, connected it to my 32" LG 4K monitor via hdmi. It came with 10.14.5 already installed. So far zero issues, have done multiple cold starts, restarts and wake from sleep while doing my migration from my old MacPro. Did have one issues during initial setup, when creating the user account the program hung. Just to make sure I wiped the disk, reinstalled osx from recovery and everything else has been working fine. Did notice the fans come on more often than the returned unit. Keeping my fingers crossed.

Hi,

I have new mac mini 2018 and I started to have a display static problems after update to 10.14.5. Waking up from sleep is all OK. I have never expect any problems. But 100% cold start-ups from power off macmini, my monitor showing weird resolutions during apple boot logo. Later in login screen I see only static like an old TV without signal. In monitor menu I can read the current resolution which is 2021x1204@60Hz !? My LG monitor supporting native 1920x1200@60Hz. I have to unplug the DVI-HDMI cable from MacMini HDMI. All is OK until next power off. Restarting are OK also sleep and wake up. I tried to connect my 32" SONY TV via HDMI and there is no problem at all. The resolution 1080i is active from fresh start. It may be that the firmware of macmini have issue with some resolutions or cold handshaking with some monitors.

after unplug and plug back DVI-HDMI cabel

I sold mine today and returned to my old 2012 Mac Mini. That machine have no issues at all. Crackeling audio problems and sync issues with monitors is just to much for me.

I noticed the monitor problems with the 2018 Mac Minis at launch in the store I work in. We sell those. I thought that would have been solved by now. I have no hope at all that this will ever be solved.

I was ever hopeful that 10.14.6 would fix the issue with two 2018 minis and two different monitors (CMV and BENQ) that worked perfectly with the 2012 minis, but no... the monitors do come back to life if left for only an hour or two, but if left for much longer, they do not awake. Monitors are connected via VGA to USB-C adapters (the 2012 minis had VGA to MiniDP adapters).

Checking the mini by logging in remotely shows that it thinks it has an internal monitor as it no longer recognises that it has an external monitor even if the monitor is turned off/on. Pulling the video cable and reinserting it does cause the mini to recognise the external monitor again - I'm just worried about the wear and tear on the USB-C connectors and so now set the monitor and mini to never sleep at the cost of power consumption.

I've had “problem solved” under 10.4.6 for quite a while now, though what really seems to have solved it was using an ancient Apple adapter just once, presumably to really confuse the thing. The fix persisted past the security updates so I'm going to call it good.

OK something weird just happened....

I grabbed another monitor Dell E2219HN FHD with HDMI input and plugged it into my Mac Mini and problem still occurred - black screen. While the screen was black, I tapped the power button a few times (between 2-6 times) and the screen came on.

To test it fully, I then did a full shutdown. Powered the Mac Mini back up and low and behold the screen turns on normally. Done this about 6 times and it turns on every single time.

I also tested it with sleep and restart - all good.

Fingers crossed this continues to work and is not just a temporary fix.