Thunderbolt cables could be to blame for LG UltraFine 5K Display issues

Cables could be to blame for LG UltraFine 5K Display issues [Update]


How's your UltraFine monitor holding up?
Photo: LG

Thunderbolt cable problems could be to blame for the issues many users are having with LG’s new UltraFine 5K Display.

It was initially believed that nearby Wi-Fi routers were the root cause of sporadic connectivity, but many are now refuting that in threads on the Apple Support Communities forum.

The issue doesn’t appear to be widespread — many units are operating without any issues — but those who are experiencing it report that their UltraFine monitor has a tendency to flicker and repeatedly disconnect from the machine it is plugged into.

In some cases, this can cause the machine itself to freeze, forcing users to restart.

LG has said it is working to “isolate the issue,” and it has recommended that users place the monitor away from their Wi-Fi router. It seems issues start occurring when the router is within 2 meters, but the monitor can go entirely black when it is moved closer.

Apple has also confirmed it is investigating the problem.

However, many users believe that their router has nothing to do with the connectivity issues they are suffering. Some report that they continue to experience issues even when the router is moved away are switched off entirely.

AppleInsider also found that placing a Wi-Fi router near to a pair of UltraFine monitors they’ve been evaluating had no effect. However, when one of those monitors was moved into a residential setting, it started seeing connectivity issues from an unknown source.

It is now suspected that Thunderbolt cables could be to blame.

“At first analysis, it may be an issue with insufficient RFI shielding on a very limited quantity of the cabling bundled with the monitor,” a source within Apple corporate told AppleInsider. “We’re continuing to look into the rare trouble reports with the monitor.”

If you have a third-party Thunderbolt cable that could have better shielding, it might be worth trying that with your UltraFine Display if you’re experiencing these issues. But here’s to hoping Apple and LG can find a proper fix soon.

UPDATE: LG’s has confirmed in a statement to Recode that it has found a fix for this issue:

LG apologizes for this inconvenience and is committed to delivering the best quality products possible so all LG UltraFine 27-inch 5K displays manufactured after February 2017 will be fitted with enhanced shielding.

Existing units will be retrofitted with the additional shielding, the company added. It’s not yet clear how customers will go about getting theirs fixed, but we recommend contacting LG.


Daily round-ups or a weekly refresher, straight from Cult of Mac to your inbox.

  • The Weekender

    The week's best Apple news, reviews and how-tos from Cult of Mac, every Saturday morning. Our readers say: "Thank you guys for always posting cool stuff" -- Vaughn Nevins. "Very informative" -- Kenly Xavier.