A seemingly growing number of users are complaining about the latest version of Apple's desktop operating system, saying it's causing freezing issues.
Mac users across forums sites, including those on Apple-tracking site Macrumors as well as Apple's own support forums, are complaining about freezing. On the Macrumors forums, alone, hundreds of people have complained about the issue. A search on Apple's forums reveals similar results.
The issue appears to be a problem with OS X 10.11.4, the latest version of Apple's (aapl) El Capitan that launched in March. Users complain that while they're using the operating system normally, it will suddenly freeze. While many people have experienced the issue in Apple's Safari browser, others say that it's also proving troublesome on both other Apple apps and third-party applications.
Macrumors, which earlier reported on the issue, says that the problem appears to be "concentrated" in Apple's MacBook Pro line. However, Apple's support forums include posts from people who are running the latest El Capitan version on several other Macs, including the company's low-cost Mac Mini.
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"The way this manifests itself is that scrolling and mouse movements suddenly start to get slow and jerky," a Mac Mini poster to Apple's site says. "Then, within 30 seconds to a minute, the keyboard stops working and mouse clicks no longer have an effect, but the mouse cursor will still move. Then it either stays that way indefinitely or the system crashes. The only recourse is to force a reboot using the power button."
Many other users have also said that the only way to fix the issue is to force a hard reboot, which requires users to hold down the power button until the machine restarts. Upon reboot, the Mac is up and running again with no issue, according to the reports.
It's unclear at this point exactly what might be causing the issue, but it seems centered on a possible bug built into OS X 10.11.4. Users who claim to have called Apple's Support team say that those folks are aware of the issue but had no immediate fix.
That said, there might be some ways around it. For one, if users have a backup of their operating system before updating to OS X 10.11.4, they can downgrade to 10.11.3, which doesn't have the same glitch. Apple also offers access to the next iteration of El Capitan, called OS X 10.11.5, though that's currently in beta and might have other issues.
It's unclear right now how widespread the problem is and whether it's something that would require such drastic measures. Many users say that it happens once a week or so, which, while annoying, might not be enough of an issue for some to downgrade to an older version of the operating system or move to the beta.
Apple did not immediately respond to a request for comment. However, the OS X 10.11.5 beta is likely not far off from being official, so hopefully that version will fix the glitch when it's launched at some point in the ensuing weeks.