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

Nov 24, 2021 7:52 PM in response to Charpie

So I too have a 2021 MacBook with M1 Max in it with an LG 27" Ultrafine 5k monitor. The LG monitor never goes to the highest resolution it's stuck at 3840x2160 so it never works at 5120x2880. Using the About This Mac and System Report and Thunderbolt/USB4 Bus 2 it shows the Speed at 20 Gb/s and it needs to be 40 Gb/s to drive 5k. The Ultrafine shows the Firmware Version is 43.1 and Link Controller Firmware version of 1.23.0. The LG Screen Manager software is the latest, but provides no way to update the LG monitors firmware. The other 2 USB4 ports show them at 40Gbs, but if I switch the LG Monitor to these ports the port speed goes back to 20Gbs.

So it looks like the OS is controlling the port speed and not letting it go to 40Gbs is my theory so possibly an OS update will fix this once Apple identifies it?

Dec 9, 2021 9:19 PM in response to Charpie

It's any m1 laptop. I've tried them all and we've been dealing with this for a year. No help from LG or Apple.


Geniuses at the bar don't seem to have any ideas.


I believe it is an LG problem with their OSX drivers. Big Sur and now Monterey have both had the issues but they seem to be sporatic and intermittent.


I haven't tried not using the hub on the back as I can't find a good hub to replace it and allow me to use my Air with the monitor.


I have a 14 Pro coming and am looking at different hubs. I love the monitor but man it is frustrating.

Dec 21, 2021 7:23 PM in response to Charpie

I also have this issue. I'm using a new LG Ultrafine 5k connected to a 14 inch MacBook Pro with 10 CPU + 14 GPU cores. Even with only a keyboard plugged in to the hub I get intermittent dropouts. As the original poster noted, once this issue kicks in the whole USB device tree on the monitor fails, meaning the speakers, camera and brightness controls stop working, along with any peripherals plugged into the monitor. Unplugging and reconnecting the thunderbolt cable rectifies the problem.


With no peripherals plugged into the monitor everything operates as expected without issue, so I've resorted to just using all the USB-C ports on the computer.


The frustrating thing is not knowing if it's the computer or the monitor at fault, I have a window to exchange the monitor but looking at the conversation here it seems that this is a specific incompatibility with M1 based machines so that seems unlikely to help.

Jan 17, 2022 8:57 AM in response to jonnybond247

While we haven't concluded where the problem is specifically, many of us are hoping and speculating that the issue lies within the firmware of either the Mac, the display, or both.


If you use a hub with Thunderbolt 3, you can run the display at 5k. You still won't be able to use the USB hub on the display, but you can use the additional connectivity on the third party hub. For example, I use the CalDigit TS3 Plus. I can use anything on the TS3 Plus without issue, including the LG display. I cannot, however, use any of the USB ports on the display itself.


You are correct, 10Gbps is not enough throughput for 5k. You need a hub that supports Thunderbolt 3 speeds: 40Gbps.

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M1 Max + LG Ultrafine 5k Issues

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