2018 Mac Mini - monitor problems

I had this problem big time for a while - what finally fixed it was plugging in a terrible Apple TB3-to-video cable. The resolution was poor, but it worked when booting, so I left it plugged in and switched to HDMI after booting. Eventually I thought "I wonder" and unplugged it - and since then the machine's been 100% OK except for the weird USB audio bug that comes in once or twice a day.

So... could be something in the built in settings that has to be overwritten somehow. I tried everything I could think of first, but that worked... still on Mojave; no plans to go further since I still use Dreamweaver CS3 just about every day.

Keep calling. Be persistent. Be obnoxiously persistent but don’t be abusive over the phone. Take note of your original case number. Make sure any new conversations are referenced to the original case number. Remind them each time how long it’s been since you’ve had the problem and how long it’s been since you opened a case.

If they tell you they’ll call back to update you on the progress but you don’t hear from them, call back and remind them you’re still having the problem.

Since I live in Spain, yesterday I sent a letter to Apple International Distribution in Ireland protesting against hardware and software problems in 2018 Mac mini.

Yesterday I discover a workaround that perhaps make your Mac wake up earlier. Under System Preferences, go to Economy an uncheck Power Nap. I hope it helps.

I wait for your comments.

When you say, “come forward,” does that mean posting here or elsewhere? I reported the problem to Apple, got no resolution, reported to LG, they offered a monitor swap (and ended up sending new cables). My personal issue was resolved when I used a nasty old Apple USB-C to HDMI connector; the screen was practically unusable but I booted with it and switched to straight HDMI afterwards. After a few boots I tried with the straight HDMI cable and it worked. Now I use the original USB (or TB3?) to DisplayPort adapter and that works fine. HOWEVER, I am having the daily USB audio problem, and about once a week it drops my TB3 hard drive — once that happens the audio also goes and then I have to reboot to make everything work.

Somewhat different problem, but info may help. I just bought a new Mac Mini (lists as 2018 model) to replace a 2014 model. On the 2014 I used an older iMac as a display, connecting with a Mini DisplayPort to Mini DisplayPort cable (Thunderbolt 2 on Mini to MDP on iMac). The iMac was kept at the login screen, and the Mini always connected to it, when rebooting or coming out of sleep.

I bought a USB C to Mini DisplayPort cable to use with the new Mini and connected to the same iMac. Found that on waking the Mini all I got was a black screen. Noticed that if I unplug the MDP cable from the iMac and then re-connect, the Mini screen comes up. Unplugging the USB C end from the Mini and re-inserting does nothing.

So it seems to me that there is a handshaking problem with the Mini when coming out of sleep; it's what is being (or not being) sent from the Mini that prevents re-connecting with the display being used. The iMac doesn't have an HDMI port, so I haven't been able to test the HDMI output from the Mini yet.

[Question: is a MDP <-> HDMI adapter bi-directional? If so, I would get one and use it to connect the HDMI port on the Mini to the MDP port on the iMac.]

The only way I've been able to use the Mini as before is to keep the display on the iMac set to 'Never' turn off at the Energy Saver screen in System Preferences. I also set up the iMac to display a screensaver at the login screen. Now I can put the Mini to sleep and after a while first the iMac login screen is displayed, and then the iMac screensaver kicks in. Waking the Mini brings up the Mini screen right away.

The iMac has to be set to 'Never' turn off the display because otherwise it goes into sleep mode with a black screen, and that is what is seen when trying to wake up the Mini.

This would seem to be something that Apple engineers could quickly diagnose and fix--just get the Mini to send the proper handshaking signal to whatever display is connected to it. When you're selling a computer without a display I would think this would be one of the first issues you test to make sure it is done right.

oday I bought and HDMI-USBc cable for the 2018 Mac mini and my LG display. It works surprisingly well. However I have a small problem. When I boot the Mac mini Apple's logo and bar do not appear. It opens directly in Craptalina's (10.15.1 update) desktop. Is that normal? It does not happen when I connect the HDMI - HDMI cable.

I have noticed that the Mac mini runs faster (at least, ti seems to me).

Finally I advise you to use a HDMI - USBc cable instead of an adapter.

I wait for your help and explanation.

Regards and thanks for your help.

In what matthewmorek writes, and like some others in this chat

about the use of old monitors and / or TV,

there is something of similar to what happens to me.

....

Like many others in this chat, I had a total blackout of my 2 LG 24UD58-B.AEU videos (linked to the mac mini 2018 via usb-c)

After many tries, I connected an old TV by HDMI and to my surprise, the old TV did wonders!!!

With Mojave 10.14.6, I have joined my 2 LG 4K LG 24UD58-B monitors with an old WGA monitor (all monitor by usb-c) and now I am able to work with some minor problems.

Now my question is: what will happen with new catalina? 

Will we receive an upgrade or a downgrade?

To tell the truth, both instances of display blackouts happened under Catalina, one during developer beta, one during public beta.

I can confirm that a combination of display factory reset, reconnecting my Mini to the HDTV and upgrading to macOS 10.15.1 has resolved the problem.

All I/O ports work perfectly now. What’s surprising under the monitor they died, so I’ve no clue.

My 2012 MacBook Pro Retina never had problems running any display over HDMI, including the one that was affected by the issue with Mac Mini.

I reckon it must be a combination of hardware and software issues, possibly with some kexts that drive Intel GPU in our minis.

Just to say my display protects its inputs by refusing an inconsistent or non-standard signal and defaulting to a blank state with “no input detected” message.

I had a problem where suddenly my computer froze (Catalina 10.15.1), and when I hard restart it, my main HDMI display (via the 2018 Mac Mini's HDMI output) would not connect with my monitor. Thankfully, my USB-C to HDMI still works. I called Apple, they asked me to put into Safe Boot mode, the display that had problems came on. Then I restarted my computer in normal mode and it currently work fine.

The question that I have for Apple is what did they break when they made Catalina. It seems like my display has problems, and my Bluetooth also have problems.

Apple support blames saying that there is something in the user kernel that causes this problem. It's hard to believe since the only thing I did was to run my regular workspace. This happens right as I was saving a file in Photoshop.

My feeling is that there has been many problems that the user more often incur with the recent updates from Apple. And Apple has been becoming more like Microsoft, where they have problems that they don't know how to fix and instead of taking it on to fix it or try to figure out this problem, they would put the blame on the user. Apple support hasn't been a professional as before.

My Mac mini is a 6-core i5, 8 GB of RAM. Monitor is a 4K LG 27UK850. This has been my experience with 10.15.1.

Wake up after sleep: it has worked most of the time. Once however it didn't. I connected the magic keyboard to charge via the lightning to USB cable. I put the Mac to sleep with the keyboard not yet fully charged and the cable still connected. Next time the monitor didn't wake up, even though I felt the Apple Watch vibrate after authenticating me.

Wake up after shut down. It has only worked twice and both times it was after an extended period of time (maybe 6 to 7 days). If I shut down and power up the next day it won't work unless I reset the PRAM.

The procedure that is working for me (Mac Mini + 27" LG, usb-c <---> usb-c cable):

• Boot: make sure the LG is awake before immediately turning on the Mini.
• Sleep: make sure the LG is awake, then press a non-printing key control, option, or command immediately.

If you are using a different monitor, your milage may vary... We may not have to be so fussy if 10.14.4 works as advertised.

I'm on 10.15.4. release and no fix - works with a TB3-DP adapter + DP-DP cable - for boot (slow to display anything prior to login) and reboot - but often fails after waking from sleep (no signal I assume, since the monitor passes the input again and again without detecting any signal). Text still looks absolute horrible compared to Win10 on same monitor.

Tried the TB3-DP cable which failed on boot - still fails on boot. Only works when freshly connected to an active Catalina, where it remains working until sleep, reboot or shutdown. Yikes the humanity of it.

Tried HDR since the monitor supports it and while it detects HDR on the input, the screens goes so dark that its useless and looks washed out. The monitors own HDR option (faking it, but still) is a lot better. Can't set brightness so useless.

A in Apple must stand for Amateurs - not sure about the rest, but Q for Quality certainly ain't part of the company name anymore

Have a bet on what A now stands for, but holes ain't part of this discussion

Turning off FileVault is not an option for me.

I have the same issue, except a somewhat larger LG monitor. The Mini recognizes my old Spectre just fine.

The ONLY way to boot is control-option-P-R.

I have 10.14.5 and problem still persists... Try with HDMI direct and HDMI-DVI ... FileVault is deactivated so that's no the problem with me... When I unplug hdmi and replug then monitor turn on ok.

https://getsupport.apple.com/

800-692-7753