The Apple Watch is increasingly becoming a useful device for both health and medical purposes. But according to a number of user reports, hospital equipment may be causing the wearable to shut down and restart unexpectedly.

Reportedly, users who work in a hospital environment are claiming that their Apple Watch Series 3 devices are unexpectedly and periodically restarting during normal use. Specifically, Apple Watch S3 owners who work in an intensive care unit (ICU) environment seem to be those who are running into problems, according to Apple news site 9to5Mac, which first broke the story.

A reader told the outlet that they had bought an Apple Watch Series 3 for their wife to check messages at her work in an ICU setting. But they added that the device regularly reboots every 60 to 90 minutes when worn in that setting. The couple even had the device swapped, but the problem persisted even with the new replacement Apple Watch.

Other users have reported similar problems with their own Apple Watch Series 3 devices in a hospital setting. Over a dozen users said they experienced the restarting issue in a single Apple Support thread posted in October of last year. The Apple Support community is littered with other reports of similar issues.

“I have the same problem. In fact, both myself and co-worker are having the same issue,” user veejl wrote on the thread. “Notice the restarting only while at work (in a hospital). While at the hospital, restarts randomly and throughout the day. At least 1x/hour.”

The problem only seems to affect the Apple Watch Series 3, with or without cellular. One user wrote that their Apple Watch Series 0 didn’t experience any issues in the exact same hospital setting, before theorizing that it could be related to certain cardiac monitors. Another user wrote that his Apple Watch doesn’t restart periodically when “away from the hospital.”

Users report that placing the wearable into Airplane Mode seems to fix the problem — but, of course, that solution also renders the device fairly useless for receiving messages, calls and other alerts.

In the Apple Watch User Guide, Apple does write that equipment such as a “pacemaker, defibrillator, or any other medical device” could be affected by Apple Watch components or radios that emit electromagnetic fields. On the other hand, Apple doesn’t specify whether issues could work in reverse — with medical devices interfering with the Apple Watch.

Since the issue seems to only affect the Apple Watch Series 3, it’s worth venturing that some internal component specific to the generation is causing the issue. But since the restarting plagues both GPS and GPS+ Cellular models, it’s isn’t readily clear what that specific component could be.

It’s currently unknown if Apple is aware of the issue. If it is a software-side bug, it’s possible that Cupertino could resolve the glitch in a future watchOS update.