2018 Mac Mini - monitor problems

It’s happening to my Samsung 4K.

I went to the Mac store after months of runaround. Genius told me there’s nothing wrong with the hardware. It’s an OS problem. He offered to roll it back to 10.14.6. He also said it’s not a widespread problem. I guess 17-page forum threads aren’t enough.

They refuse to take any responsibility.

Yeas, it's happening to my BENQ LED non-4K monitor and to my wife's CMV LED non-4K monitor too (both using USB-C to VGA adapters). Both monitors had no problem with two 2012 Mac minis. Both monitors fail to wake with two 2018 Mac minis.

I don't believe it's a operating system issue; I suspect it's a firmware issue. Looking at you T2.

> He disappeared and came back with an ancient VGA monitor with an HDMI adapter and of course it worked.

Interesting. I'll try an HDMI > VGA adapter on my non-4K monitors and see if it helps (currently USB-C > VGA adapters).

> I told him it’s a 4K problem.

No - it affects non-4K monitors too. Both mine with the issue are non-4K.

I tried to return the mini i7 to an Apple store. This was three weeks after I bought it and huge problems with FileVault. Encryption and 4 k monitors. You all know the problems

they refused to take back this piece of defective equipment. Why? They said that since I bought it from B&H photo then it is not apples problem

that Said they replaced the motherboard. That fixed the monitor issue. But now with 10.14.6b and Catalina, it is all going downhill again

terrible. This is truly the first Apple computer that does not reliably work as advertised

A recall of all i7 mini should occur and a credit given to purchase another Apple computer. Or they extend the warranty for 3 years and actually fix the problem

Catalina Update today.. Don't get excited, issue is not fixed for 4K LG's. I thought it was fixed because the monitor stayed on throughout the entire update, when I initially updated to Catalina the monitor turned itself on and off automatically through updates but never happened to actually come back on the 4K.. I had to unsafely power down my Mac Mini 2018 then plug HDMI into a 1080P Asus display> can boot from there> switch HDMI cable from 1080P monitor to 4K monitor, BUT do not turn off computer, only let sleep, and monitor will wake up after waking monitor twice with your mouse!!! What a nightmare right?! I also got a hold of Apple and they claimed they could not read this thread!!

Mario

welcome to the discussion. Sorry you had to join.

if apple will refund your money, return it, and do it today. Get an iMac or a Lenovo or something else. Stay away from the mini

otherwise you will be another of the 18,000 posters on this site who complain about cables,

Black / blue / purple screens/ FileVault. / missing external hard drives, etc.

this is ongoing for 8 months for me, and Catalina makes it worse

when you take your mini to the Genius Bar, they plug it in with their own hdmi HD monitor, and it works

so they won’t replace the mini and they won’t refund.

dont fall for this. You must insist on a full refund and forget about the mini.

best of luck

Update: Going from HDMI on Mini to MDP on iMac with an adapter didn't work. Not even a hint of a connection, like a screen flicker or anything else.

On the other hand, was able to establish a connection from a MB Pro to iMac via the USB C to Mini DisplayPort cable. So this is not a cable problem and is definitely a 2018 Mini problem for me. Since I just bought the Mini this past week, I'm strongly considering just sending it back for a refund and will wait until they find and correct the problem before upgrading.

Since I live in Spain, two weeks ago I sent a letter to Apple International Distribution in Ireland. Yesterday I received a letter from them. It seems they are very interested in speaking to me. However, I am NOT ready to spend two hours or more on the phone explaining all the stuff again. My time is also of great value.

In my opinion, since it seems Apple is not going to solve our HDMI problems in the short term (it seems it is not enough important to them) I propose you to send letters directly to the president of the company. I am going to do that. I am sure that if Mr. Cook receives 200 letters all over the world about maca mini's problems he will pressure the engineers to do something. It also possible that he is not conscious with the problems arising from HDMI's Mac mini.

I am going to do that. I hope we all have our problems solved.

I had this same exact issue with my 2018 Mini and my Dell 28” S2818Q 4K Display on HDMI-HDMI. It intermittently would not wake from sleep and since upgrading to Catalina stopped working from a cold boot altogether. The fix was to connect it to my TV and plugged it back into my monitor. But issues persisted...

It would take 20 seconds or so to wake from sleep, if at all. So I bought a USB-C - DisplayPort cable. And while the picture quality isn’t as good, it works 100% of the time. But I still have one issue...

My Mini is still slow to wake the display from sleep. It takes 7 seconds each time to wake it.

Any suggestions? I can try resetting SMC but not sure that will work.

Thanks

I just bought a new Mac Mini and my ten-year old LG 2250 monitor was not happy. It would work occasionally but was unreliable. I took the Mini back to the Apple Shop and it worked fine with their monitor. I bought a new D-Sub cable - still no joy. I connected the monitor up to my 21 inch iMac as a second screen and it worked fine. I concluded that for some reason old LG monitors are not compatible with new Mac Minis. I have now bought a new LG monitor and it works fine. Hope that helps.

On my system with Catalina 10.15.1 there is no Problem at all!

But - if FileVault2 is activated you must switch on your monitor first and the mac mini after that - otherwise he does not recognize the screen.

I have a similar rig:

 Model Name: Mac mini

Model Identifier: Macmini8,1

Processor Name: 6-Core Intel Core i5

Processor Speed: 3 GHz

Number of Processors: 1

Total Number of Cores: 6

together with the same model monitor, connected usb-c <--> usb-c cable supplied with the monitor.

To awaken a sleeping system (both mini and monitor) I tap either the option or control key two or three times. Seems to awaken mini within 7 - 8 seconds.

Mine was fixed with 10.15.2 and continues to work fine on HDMI to HDMI with 10.15.3. Still not fixed is the USB-C to DisplayPort connection, but that's another battle. At least it's working for me on HDMI. It must depend on monitor brand and type and the ability to handshake with the Mac.

Mine is a Samsung 28-inch 4k monitor model LU28E510DS.

I get pretty good display quality using USB-C to DisplayPort - far better than via HDMI (it's an HDMI 1.2 monitor, I think, which is part of it). Check your scaling and such. I find it takes a while to wake. I have full disk encryption on, so for me the monitor does wake up before the login screen. It is incredibly slow to wake from sleep, though, which on reflection is probably a scaling/handshake issue.

Nothing related to TB3-DP seem to have changed in 10.15.4 at all

While I found an adapter that seemed to work, its still busted functionality:

• Boot: Won't ever see the Apple logo - no input until logon screen on DP - HDMI works as it should
• Wake from sleep: Will sometimes crash the TB3-DP interface and nothing will get the screen to detect input on DP
• Switching inputs: Usually works - unless the iMac mini have been in sleep mode - otherwise crash TB3-DP interface

When the TB3-DP interface crash, not even unplugging and replugging the cable will work

Giving it the HDMI cable will give input

No FileVault at any time

I miss Steve Jobs and his focus on quality for price. Now its just for price and a logo.