10.15.6, external display problem

I just discovered this thread. There is another thread about the same topic, but this seems more active.

I'll state my problem:

Hardware:

MacBook Pro 16"

• 2,4 GHz 8-Core Intel Core i9
• 64 GB 2667MHz DDR4
• AMD Radeon Pro 5500M 8 GB
• 4Tb SSD

All external Displays I tried this with (all result in the same Problem):

• AOC Q27P1
• Lenovo LT2452pwC
• HP EliteDisplay E242 Monitor
• Dell U2412M
• Dell 1907FP

Adaptor I have this problem with:

Belkin USB-C to VGA adaptor (F2CU037)

This Problem immediately occurred after the update to macOS 10.15.6. I had a display connected right before the update (it was working perfectly) and right after the update (that's when the problem first occurred).

This is a very strong correlation for me. The adaptor works fine with a surface book and all the above mentioned displays, which leads to the conclusion that the problem lies with the macOS update.

When I plug in a Monitor via the adaptor all connected displays and the internal display start to flicker as if they can't properly be detected. This goes into an infinity loop with a flickering pattern (internal display lights up for 1/10 of a second and goes black for 1 second).

I have tried everything mentioned in this thread including rebooting in safe mode, resetting NVRAM and PRAM, etc.

The update to 10.15.7 did not solve the problem.

Of corse I can just buy a new adaptor that supports DP or HDMI (my Belkin HDMI adaptor works just fine) but I think we all agree that this is not acceptable if I spend 6k for a laptop. I have to rely on this adaptor for presentations if there isn't a HDMI available for the projector. So I bought the apple adaptor. But no one can seriously suggest that this is a solution.

Addressing the comments that the adaptor wasn't supporting high speed transmission or a certain resolution or isn't certified. Sorry but this is nonsense. First of all this adaptor worked perfectly fine previous to the update. Second Belkin is a premium brand that supports all standards. Especially with VGA its not a problem of any speed restrictions. With 4k this might be a different story but not VGA.

I will go to an apple store next week, let's see what they have to say. I am really disappointed with apple on this one. I just expect not to bother with something like this.

Update: After consulting this guide, I tried restarting in Safe Mode. In Safe Mode, I was able to connect the monitor successfully. I just restarted in normal mode, and the monitor is also connecting successfully.

However, it might just be fixed because I restarted (a few days ago, I was able to temporarily fix the problem by restarting). So I'll see whether this fix persists or not.

You can't expect to get high resolutions from either of those displays when you connect them via Analog VGA. it is simply too weak and no one is testing it any more.

If you complain long enough and hard enough, you will force Apple to revise their specs to say they no longer support Analog VGA connection. they will NOT fix this.

Both of those displays support [Full Size] DisplayPort input. you should use a cable that also converts from the computer's USB-C port to the display's DisplayPort input, and your troubles will disappear.

Apple sells this one:

Moshi USB-C to DisplayPort Cable $49.95

MonoPrice sells this one:

Monoprice USB Type-C to DisplayPort 3.1 Cable - 5Gbps, Active, 4K@60Hz, Black, 6ft - Product # 24444 - $22.24

I am sure there are others as well.

If you prefer, you could connect using HDMI, a consumer-level interface, but getting the correct cables is more complex.

SUCCESS! (?)

Well, I broke down and purchased a USBc to VGA Belkin adapter and this monitor now works. For those struggling with this issue, this isn't a solution to the original problem, but it works. I bought it from the Apple Store for $32 dollars. Is it worth $32 dollars? I would say so if it gets my monitor up and running. Is it good that I needed to spend $32 to get a monitor working because of an OS update? No... but you may think otherwise.

Link to the product, which you can probably get at half the price elsewhere is below. (but I wanted Apple to own this if it didn't work so I bought it through them...)

https://www.apple.com/shop/product/HJUZ2ZM/A/belkin-usb-c-to-vga-adapter?afid=p238%7CsDb8WwLtF-dc_mtid_1870765e38482_pcrid_246387003261_pgrid_49565832687_&cid=aos-us-kwgo-pla-btb-3pp--slid---product-HJUZ2ZM/A

We're getting served the (by far) most common answer on discussions.apple.com, which is: reset PRAM / NVRAM / SMC and the like. Of course this is not fixing the issue so we're being told: change the hardware. I haven't learned a single thing from this thread. The problem lies unresolved.

Read the thread again: PROBLEM OCCURRED RIGHT AFTER 10.15.6 UPDATE. Hence, there is a CLEAR cause and effect relationship between the update and the occurrence of the problem. AND YOU CAN'T EASILY DOWNGRADE so you're stuck in a dead end. The only way out is spending more money for a solution that *might* solve the issue, possibly for a little while.

Apple is one of those companies that REMOVE features as time go by. USB 2, Ethernet, DisplayPort, Thunderbolt, MemoryCard slot... Back in the days, Messages app connecting to other chat services and so on. The list goes on forever. Next iPhone won't even ship with an adaptor. Stunning. Be prepared for a mandatory subscription to Apple Services to be able to turn on your 5000$ MacBook Pro.

In between 2 workouts in the $ 120 million gym at Apple Cupertino, a very smart Apple PO has decided that nobody needs a non-USB-C external display after all. "Let's get rid of that feature, make adaptors useless so we'll boost USB-C display sales".

This is Apple, a dictatorship that can't possibly be wrong. Right? The best propagandists for it is the flock of those who *think* they know better.

• Karen

I've downloaded and installed the DisplayLink driver but no solution so far. I'm not able to see the DisplayLink driver in the Screen Recordings section of System Preferences. Is this what you see?

Thanks!

I just updated today to 10.15.6 (16 inch Macbook Pro) and now my external monitor will not work. When I plug the monitor in, both screens go blank. Tried rebooting and that did not work. Put the laptop in Sleep mode and then out of Sleep mode and that did not work either.

Monitor works fine on other laptops and no other updates are available.

Really need this fixed as working from home without an external monitor is less than stellar.

This is happening to me too! I've used the exact same laptop, HDMI cable and monitor for months with no problem, but this week after the update, when I plug in the external monitor, both screens go black, with occasional flickering where they show the display for a moment.

Update: The Safe Mode fix did not last; I still have the same problem. Will Apple be doing something about this? Especially at a time when so many people are working from home, not being able to use external monitors is a huge productivity problem.

Same problem here on my 3 months old 16", and nothing seems to fix it. I'm telling you: Apple is going down the drain. The accountants have taken over. My previous laptop was a 15" mid 2012 that is still running perfectly to this day although with an SSD upgrade. This 16" MacBook Pro keeps disappointing me day after day.

I think that this external display not working after the 10.15.6 update is actually a fix for another problem with the 16": when connecting an external display both fans just go wild and make this humongous, unbearable noise. No external display, no more noise. See???

MacOS has the capability to test the connection to the display, to determine whether the cable is adequate. If your cable is not certified for the high speed of the display, it could fail to light up.

If Apple tightened the specs on cables, that could explain why it is no longer reliable.

Sure, we are all thrilled, and really look forward to pay 79 $ + tax and shipping for a piece of plastic with an Apple logo on it instead of a 15 $ knock off. And all this after paying 4000$+ for a loaded MacBook Pro that did not even come with a power cord extension. This is all getting ridiculous.

The good news is that, based on history, those Apple adaptors are likely to stop working as well when the ARM models come out. Or OS 10.17, or, basically, whenever this dictatorship decides.

I said nothing about Apple parts.

HDMI cables are available in standard, High speed, and Ultra-high speed. Using one at resolutions beyond its certification could cause your display to perform badly, or not at all.

Dell has posted a warning that certain of its displays do not work reliably with certain HDMI cables longer than 5.9 feet.

Again, the whole set up was working absolutely fine prior to the 10.15.6 update. PRAM/SMC resets and all the usual tricks do not fix the issue. It is definitely related to the update. Problem is, downgrading to 15.5 is overly complicated and time-consuming.

When one pays a premium price for a computer, or any object or service for that matter, it must deliver a near perfect performance, period. Otherwise it feels like theft.

MacBook Pro (16-inch, 2019)

2,3 GHz 8-Core Intel Core i9

32 GB 2667 MHz DDR4

AMD Radeon Pro 5500M 8 GB

Intel UHD Graphics 630 1536 MB

I.T. Works model 4253132 USB-C to VGA, USB 3.0, USB-C

VGA cable

Dell P2314H 21 inches or Dell UltraSharp 2405FPW 24 inches, same result