For new MacBook Pro customers desiring an external display, Apple now recommends the LG UltraFine 5K Display, having discontinued its own Thunderbolt Display last summer after spending half a decade on the market. LG's UltraFine 5K Display has a Retina resolution in the vein of 5K iMacs, and it connects via the new Thunderbolt 3 I/O.

There is, however, a critical usability issue with the UltraFine 5K Display that isn't found on other external monitors: the display can become unusable if placed within proximity of a router — about 6.6 feet, to be exact.

LG UltraFine 5K Display Hardware Problem

Apple introduced the UltraFine 5K Display during its MacBook Pro event this past October, saying that the monitors were a collaboration between the company and LG. For some Mac loyalists, the new monitor is the closest thing they can get to a Thunderbolt Display alternative.

At 27-inch, the display is a behemoth. It's able to output a resolution of 5,120 x 2,880, like the Thunderbolt display, and the UltraFine 5K Display is gorgeous and sharp thanks to the Retina display, a term Apple first coined for screens with a high pixel density.

The Router May Be The Culprit

9to5Mac's Zac Hall began experiencing problems with his UltraFine 5K Display last week, when the device started to disconnect randomly and even freeze the MacBook Pro it was tethered to. A review for the Display posted by user Patrick G on Apple's website pointed him to the potential cause behind his monitor problems.

Hall's MacBook Pro is situated within proximity to his router, so his UltraFine 5K Display is logically within the same workstation. The reviewer states that the monitor stopped having problems once the router was placed far enough from the display.

Hall performed a similar setup, testing his display in another room, which worked. The display became functional when placed nowhere near his router. Hall contacted LG's customer service about his issues without mentioning that it could be caused by the router.

The company responded by suggesting to Hall that he distance the display from the router, because it may affect its performance. He did as such, and the display hasn't had issues since.

LG says the issue only affects its 5K monitors and no other LG displays. Without ample proliferation of 5K Displays on the market, it's difficult to test whether this is an overarching problem tied to all 5K displays, or just LG's hardware mishap. The fact that LG knows the issue without Hall's mentioning of it is evidence enough that other customers may be contacting the company's customer service for similar problems.

Moving the router away from the Display is of course very feasible, and would probably not be a major nuisance for some, but the more pressing concern here is, why does the issue even persist? Could this be a blunder in the product's engineering, or an isolated case? The review mentioned by Hall seems to support that the issue is at least experienced by more than one person, which could balloon if more people come to the fore.

Until then, if you have a malfunctioning UltraFine 5K Display, consider moving the router away and see if it functions properly afterward.

The LG UltraFine 5K Display is available from Apple's website at a discounted price for a limited time only.