Owners of the GoPro Karma have been unable to fly their drones since the new year began, according to dozens of forum posts and tweets. The problem is affecting owners all around the globe, and it seems to be related to the recent so-called clock “rollovers” in the GPS and GLONASS satellite systems. While most tech companies tried to avert problems with the rollovers by issuing software updates over the last few months, GoPro has not updated the Karma since September 2018, nine months after it discontinued the drone.

Multiple owners say their Karma controllers are flashing errors about not receiving a GPS signal, and that they can’t calibrate the compass. They’re not able to fly the drones at all, even after disabling GPS, though one claims to have sidestepped the issue by factory resetting the controller and turning GPS off. A GoPro spokesperson tells The Verge that the company’s engineering team is “actively troubleshooting” the issue, but didn’t offer any more information.

We will definitely post an update once we hear back from our product team. Thank you for your patience and understanding. — GoPro (@GoPro) January 5, 2020

Here’s how our own James Vincent described the GPS rollover issue last year:

The rollover issue itself is caused by the fact that GPS systems count weeks using a ten-bit parameter. This means they start counting at week zero and reset when they hit week 1,024. The first count (or “GPS epoch”) started on January 6th, 1980, and the first reset took place on August 21st, 1999. That means the next one is due April 6th this year. When the rollover happens older devices may reset their date, potentially corrupting navigation data and throwing off location estimates. GPS relies on precise timing data to operate, and each nanosecond the clock is out translates into a foot of location error.

GLONASS has a similar problem counting days after a certain amount of time, and is said to have reset at the end of 2019 (or the start of 2020).

Related Older GPS devices are facing their own mini Y2K bug next month

GoPro had problems with Karma from the moment its first (and now only) drone went on sale back in 2016. Some of them were falling out of the sky just weeks after the October 2016 launch, thanks to a poorly designed battery latch, and GoPro recalled the drone on the night of the 2016 US presidential election. The company struggled to find market share with Karma once it was back on sale, but it ultimately wasn’t able to turn enough of a profit on the drone to justify keeping the program up and running.

GoPro exited the drone business in January 2018 and laid off hundreds of employees who worked on Karma. The company said at the time that it would “continue to provide service and support to Karma customers,” though it never mentioned when that support might end. It’s unclear how many owners might be affected as GoPro never disclosed the total number of Karma sales before or after its discontinuation.