While iPhone problems may be fairly common, it’s much rarer for the Apple Watch to experience widespread issues. But the newest models are reportedly experiencing an issue with the display that has Apple working on a fix.

According to an internal service memo shared with MacRumors, Apple is investigating an issue where the display flickers or “pulses” on some Apple Watch models when Always On mode is enabled. Sporadic reports around the web from both Apple Watch Series 9 and Ultra 2 users have complained about the issue, including some saying their complications “flash pink” when raising to wake. Another report says the issue occurs “when a timer is running and when on the Modular Ultra face.”

Apple has advised service providers to not repair the device as the issue appears to be tied to software rather than hardware. There are reports that the latest beta for watchOS 10.1, which will arrive early next week, fixes the issue.

The Apple Watch Series 9 and Ultra 2 arrived in September alongside the iPhone 15. Among the changes over last year’s models are a brighter display and a significantly more powerful processor.