M1 Max + LG Ultrafine 5k Issues

I seem to be experiencing some compatibility woes. My 14" MacBook Pro M1 Max does not play well with the LG Ultrafine 5k display.


Devices plugged into the display's hub will ultimately fail and become unrecognized; the camera will ultimately fail; the speakers will ultimately fail. The display panel itself works just fine, however.


It's quite frustrating and I've had to resort to my 16" Intel MacBook Pro as my daily driver to get work complete until this issue is resolved. Everything with the display works completely fine with the 16" Intel MacBook Pro. In fact, everything works completely fine with my 13" MacBook Pro M1 as well. All machines are running macOS Monterey. Only the M1 Max machine doesn't work with the display.


I've tried pretty much everything I can think of at this point:


  • Tried various Thunderbolt 3 and Thunderbolt 4 cables. Even bought new ones. Didn't make a difference.
  • Tried various USB cables plugged into the display's hub. Devices still failed.
  • Checked the firmware version of the display to make sure it's up to date. It is.
  • Erased the Mac and started from scratch. No help there.
  • Tried plugging the display into all 3 Thunderbolt ports. Behavior is the same across all ports.
  • Installed older drivers for the peripherals plugged into the display. Nope.


The LG Ultrafine 5k works just fine. It behaves like a champ on two other machines across both Intel and Apple silicon.


Without a doubt, this is either a compatibility issue with the M1 Max machines or a specific hardware failure with my 14" MacBook Pro.


Posting here to see if others are having a similar experience or can perhaps provide further insight.


Mac Info:


Model Name: MacBook Pro

Model Identifier: MacBookPro18,4

Chip: Apple M1 Max

Total Number of Cores: 10 (8 performance and 2 efficiency)

Total Number of GPU Cores: 32

Memory: 64 GB

System Firmware Version: 7429.41.5

OS Loader Version: 7429.41.5

OS: macOS Monterey 12.0.1

MacBook Pro 14″, macOS 12.0

Posted on Nov 23, 2021 7:48 AM

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Posted on Mar 10, 2022 10:52 AM

After a new OWC Dock to replace my Elgato, 2 main board replacements in the LG, a logic board in the M1 Air, as I reported the LG failed again in my office but worked upstairs in the house.  I concluded there must be some kind of interference in the office, where I’ve got “command central” with wireless wifi hvac and security control centers, Time Machine, OWC Thunderbolt dock/ac-dc power supply, printer, ethernet switch modem/gateway, Panasonic cordless Bluetooth base station, UPS powered USB connected wireless KEF powered speakers (connected with usb), wireless garage door entry, a rechargeable portable weather radio, a wireless motion alert, an iphone magnetic charging stand and I think that covers it. 


To try and cut down on visually on all the wire nest clutter I used white cables wherever I could and if that was not possible I covered them in white split loom cable covers.  Extra cable was coiled and zip tied and I gathered different cables together and held them together with Velcro ties.

 

I did extensive research on what the interference could be and discovered it could be RF (radio frequency), Bluetooth or other

things.  I purchased Faraday fabric and tape for the RF to use as an RF shield, but so far haven’t used them.


Finding what exactly is interfering with the monitor is a process of elimination. Here's what I did so far.

 

1.    Unplugged the Bluetooth cordless phone base station and moved the laptop further from the monitor (Bluetooth can cause interference, but the wireless keyboard and trackpad are still in use)

 

2.  Installed ferrite chokes on all both ends of power cords that did not have them; these are RF traps


3.  Added surge protectors on all power outlets that did not have them where things were plugged in but not plugged into my Cyberpower 1500VA UPS (surge protectors have RF filters but not all power strips do)


 4.  Moved the weather radio and wireless motion alerts about 15 ft. away (discovered both of these use the 900mhz frequency and while I did not read that this band is a problem, since I could do this and unclutter my desktop at the same time, I did so)


5.    Moved the Apple Time Machine further from the monitor, but still about 3 ft. That's what LG said to do initially in 2017 when they found the monitor did not have proper (or any, they never said) rf shielding inside (apparently it's a plate that covers the main board)


 6.    Unclipped the zip ties from any coiled cables (coiled cable can pick up RF) and removed Velcro ties from cables bundled

together


I had the monitor connected directly to my Macbook Air M1 and the monitor worked!  That is, for about an hour before I had my first crash, with the same 35 second timer error message yet again with the same 35 second issue. My KEF powered speakers had knipshins since only the wireless connection was available. I had the speakers wired connection plugged into the OWC Dock which since I did not have the LG monitor connected to the dock could not work via wired USB. I tried connecting the speakers that way, which I had for years with my Elgato Dock, and they went crazy, switching randomly from wired to wireless.




Now what I am going to do is to move the OWC Dock further away and try it as it is intended to be used, which will be less convenient and in fact require longer cabling. Or I may try it covered with some Faraday shielding fabric. Or get rid of it and go back to a non-powered hub. Or relocate it under my desk (which is a 1 inch piece of quartz Silestone, but shielded with the RF fabric.


And, there's a great article here: https://www.signalboosters.com/blog/wifi6-the-next-generation-of-wifi/ on Wifi 6 and I'm going to get ATT to upgrade me to their new Wifi 6 modem/gateway whatever it takes, since the Macbook Air M1 and iphone 12 has wifi 6. What I learned from this article is that Wifi 6 is not just about speed, but it's as much about less interference from wifi signals, including from neighbors and especially if in close proximity, and a better focused signal, which also lessens signal interference.


I'm encouraged so far that I may, and I say may, have found the source of the problem. I'll keep posting and I hope this helps. I hope that the new Apple Studio Monitor released this week doesn't suffer the same fate as the LG Ultrafine 5k. I'm assuming at least part of the monitor was made by LG. Given inflation over the last 5 years, it would be priced at $1500 vs. the LG Ultrafine 5k's $1300 original price. With the Studio's improvements, it's a good value in comparison.






Similar questions

97 replies

Jan 15, 2022 8:55 AM in response to Charpie

I am having the exact same issues on my two LG 4K UltraFine monitors.


I am running:

  • MacBook Pro 14"
  • Apple M1 Max
  • 64GB ram
  • 64 GPUs
  • macOS 12.1


I was running (it worked just fine with this machine):

  • MacBook Pro 16"
  • Intel i9 2.4
  • 64GB ram
  • macOS 11


Connected to my monitors:

  • 2TB SSD
  • 4K Logitec Webcam
  • Mechanical Keyboard
  • iPhone 6S
  • Android Pixel 4A
  • iPhone Magsafe Charger
  • Apple Watch Charger


I have tried the following:

  1. Using `LG Screen Manager` to factory reset the monitors (did nothing)
  2. Using `LG Screen Manager` to `update` the monitors (there was none)
  3. I thought it was a power issue so I used magsafe (did nothing)
  4. I tested using Prime95 to stress the MacBook (caused the issue to happen quickly)
  5. I only connected certain USB devices to the monitor hub (all causes issues)
  6. I used one monitor and tested (single monitors have the same issues)
  7. I checked `ioreg -p IOUSB -l -w 0` and validated the MacBook still saw the IOUSB devices (devices are there)
  8. I downloaded `LG Onscreen Control` (did nothing)
  9. Tried various cables (did nothing)


Jan 17, 2022 6:36 AM in response to Charpie

Same issue here. On M1 Max MBP the LG 5k Ultrafine display get all USB devices disconnected from time to time (i would say almost every hour).


I have an Intel 16" MBP and this issue does not happen (this MBP is still running Catalina) when plugged to the same monitor with the same devices connected.


I hope this is a software issue that can be solved either by LG firmware or Apple Mac OS X update.

Jan 25, 2022 3:58 PM in response to Charpie

I dont think these problems are limited to the 5k ultrafine and the M1 Max.


I have an M1 Pro 14 and an LG Ergo 32” 4K. Works fine until I reboot or if my computer goes to sleep. Then loses signal entirely. My workaround is resetting the monitor to initial settings each time I reboot or reconnect. It is maddening. And this is just a $700 monitor, not the expensive 5k ultrafine which I would be furious about.

Feb 24, 2022 2:23 AM in response to Charpie

Hi Charpie,


I have similar problems with my MacBook Pro 14" and my LG UltraFine 5K.

The UltraFine 5K worked flawlessly since I bought it. For the past two years I had attached my MacBook Pro 16" (Intel CPU) to it and had no problems. The day I switched from the 16" Intel MacBook Pro to my new MacBook Pro 14" (M1 Max CPU) I experience problems.


The MacBook Pro 14" loses connection to the display without any warning. The display goes black and the MacBook Pro goes into sleep.


This is really annoying and I hope Apple will fix it very soon!


Mac Info


Model Name: MacBook Pro

Model Identifier: MacBookPro18,4

Chip: Apple M1 Max

Total Number of Cores: 10 (8 performance and 2 efficiency)

Total Number of GPU Cores: 24

Memory: 32 GB

System Firmware Version: 7429.81.3

OS Loader Version: 7429.81.3

OS: macOS Monterey 12.2.1


Display Info


Model Name: LG UltraFine 5K

Device-ID: 0x1114

Device-Revision: 0x2

Firmware Version: 43.1

Firmware Version of Link Controller: 1.23.0

Feb 24, 2022 8:11 AM in response to kriheli

to get a Mac display to become active, you need the Mac to query the display, and the display to answer with its name and capabilities. Otherwise, the display will not be shown as present, and no data will be sent to the display. "No signal detected" is generated by the DISPLAY, not by the Mac.

 

This query is only sent at certain times:

• at startup

• at wake from sleep — so momentarily sleeping and waking your Mac may work

• at insertion of the Mac-end of the display-cable, provided everything on that cable is ready-to-go

• on invoking Option-(Detect Display) button in Displays preferences (from another display)

 

so try doing some of those things and see if the display comes alive.


Modern Displays with multiple ports are sometimes busy scanning the other ports, looking for an input, and miss the query from the Mac. They need to pay attention to the port you are actually using, or they will miss the query.


Some displays have On-Screen Display settings that can be used to tell the display a computer is attached on a certain port, or a certain port should be highest priority. Changing those may make your display more responsive.


Some displays include their own private "sleep" settings for the display alone. This can allow the display to enter its own sleep mode, on top of the Mac's not sending it data. A display that is sleeping on its own cannot respond to the Mac's query, and will stay dark.


--------

My speculation:

In the M1 Macs, there may be different order of things becoming active, e.g, the ThunderBolt ports may not be ready as quickly because the Hardware used is different from previous models. This could be causing the query to be sent before the Thunderbolt ports are ready to send/receive the response.

Mar 10, 2022 9:21 AM in response to Grant Bennet-Alder

Just hit the same problem. However, I have TWO LG Ultrafine 5k displays. One connected to a left-side TB4 port, one connected to the right. The one on the right is rock-solid stable (main display), while the one on the left (extended display) keeps on connecting and disconnecting. When I use videoconferencing apps, they can't see the camera. I was using the LG-supplied cables, and had it connected to an OWC Thunderbolt hub.


Things had been working just fine since Jan 18 (when I got the monitors), and only in the last week or so have things gone to **** in a hand basket. I have tried removing everything from the monitor hub, tried connecting the monitor directly, tried using Apple's 0.8m TB cable - both directly and from the laptop --> hub AND hub --> monitor (i.e., 2 cables).


I'm still seeing the same problem (or at least I saw it prior to adding the 2nd 0.8m TB3 cable about 20 minutes ago; nothing since then, but I'm not optimistic).


Nothing really useful to add here other than the fact that I seem to be one of the few with 2x LG Ultrafine 5K displays and only one of them is exhibiting this problem. @matthew8139 - did you hear anything further from Apple or LG?

Dec 13, 2021 2:06 PM in response to Charpie

Just giving another update. There is still no fix, but for some reason the situation has gotten worse. The display now sometimes causes a kernel panic, which is actually the first time I've heard the MacBook's fans kick in. 😆


LG Screen Manager, the awful LG app, now states the display is not compatible. Previously, I was able to use the app to check the firmware version, but this is no longer the case.

Jan 2, 2022 2:30 PM in response to Charpie

Same issue; so far have replaced main board in monitor, purchased new thunderbolt dock and new thunderbolt 3 cable with correct specs; downloaded new LG Screen Manager software version 2.90 and connected Macbook Air M1 directly with monitor. Still getting on/off screen, open/close clamshell to start monitor, and kernel panic crashes. Very frustrating, especially when no one responds.

Jan 17, 2022 8:24 AM in response to Charpie

Is the problem with the display hub or the M1 and monitor not being able to communicate effectively at speeds high enough to adequately and reliably run the monitor at 5k resolution? If you use an external hub with thunderbolt 3 capability, does this both allow the monitor to run at full 5k resolution WITHOUT all of connectivity issues described here? I saw a link to one of the hubs in this thread which seems to output at 10gb- which I thought was not enough to run the monitor at full 5k resolution (ie the monitor is running at a lower resolution)- which is why it might have worked as a solution. If buying an external hub with thunderbolt 3 capacity is actually a solution (nowhere near ideal- I grant you that) for running the monitor at full resolution without issue, it would be good to know as a possible option. Thanks

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M1 Max + LG Ultrafine 5k Issues

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