I've noticed my OS X system time on my iMac is running faster after I updated to Mavericks, after about a week it is a good 4 or 5 minutes too fast.

In my Date & Time preferences everything is set to automatic, time is set to update using Apple Europe (time.euro.apple.com.) and the time zone is set to automatic too.

Any idea why this could be happening, and how to fix it?

  • It could just be that the internal clock battery is dying. Automatic time sync doesn't happen continuously. How old is your iMac?
    – NReilingh
    Nov 20, 2013 at 5:52
  • I bought it around March 2010. Never had this issue before with older macs though :-/ Nov 20, 2013 at 10:18
  • It'll definitely happen eventually, but yeah, 3.5 years is way too short. Curious.
    – NReilingh
    Nov 20, 2013 at 14:59
  • This has been bugging me for the last few weeks as well. Over the long holiday weekend my system was off by 5 1/2 minutes. Opening the date/time preferences pane causes it to sync immediately. I called apple support regarding this a bit ago; they had me reset the BMC and PRAM. I'm running a script every 5 minutes to track the differences between my system clock and their time server. After 5 minutes it's clear it's running too fast and not syncing up to ntp as it should. This is a Late 2012 iMac I've had for only 3 months (as a replacement for another iMac apple couldn't fix).
    – yoonix
    Dec 2, 2013 at 20:49
  • @yoonix Shame that resetting the BMC and PRAM didn't work as I hadn't tried that yet. Tempted to set a script to run ntpdate every few hours but I'd rather find out what the problem is! Dec 4, 2013 at 11:14

2 Answers 2


My iMac suffered from the same inaccurate clock syndrome. However my MacBook Pro set up exactly the same with Mavericks and on the same network keeps time very well.

The problematic iMac was reporting an inability to "create socket" in the system.log. It looks like it was trying to set the time every 5 minutes when I looked in the system.log

$ grep ntpd /var/log/system.log    returned many of these, each about 5 minutes apart:

Dec 19 15:32:46 Macintosh-0023dffe31b2.local ntpd[8887]: unable to create socket on en1 (53) for 2002:43ba:cb7b::a82a:82b9:92d0:134#123  
Dec 19 15:37:47 Macintosh-0023dffe31b2.local ntpd[8887]: unable to create socket on en0 (54) for 2002:43ba:cb7b::701a:38b1:c1e9:db4d#123  

As a shot in the dark I changed the time server in the Date & Time prefs by pasting a server from a near-by city over the Apple (time.apple.com) entry. I used ntp-nist.ldsbc.edu.

Now the time is updating periodically and seems to be accurate.

$ grep ntpd /var/log/system.log now returns entries like these and looks like it is updating the time appropriately:

Dec 19 15:53:15 Macintosh-0023dffe31b2.local ntpd[124]: proto: precision = 1.000 usec  
Dec 19 15:57:43 Macintosh-0023dffe31b2.local ntpd[124]: SYNC state ignoring -0.128408 s  
Dec 19 15:58:49 Macintosh-0023dffe31b2.local ntpd[124]: SPIK state ignoring -0.159852 s  
Dec 19 16:19:45 Macintosh-0023dffe31b2.local ntpd[124]: ntpd: time set -0.224141 s  
Dec 19 16:55:43 Macintosh-0023dffe31b2.local ntpd[124]: ntpd: time set -1.573103 s  

I hope this continues to solve my problem.

  • Well, it didn't stick. My clock drift is back and the system log shows that the computer is again "unable to create socket" So just changing the time server fixed the problem for about a day but is not a permanent solution. The computer is running 10.9.1.
    – user283368
    Dec 23, 2013 at 22:26

I fixed this issue by adding the following line to /etc/ntp.conf

interface ignore ipv6

and then restarting ntpd.

It appears to work just fine using ivp4 instead of ipv6

  • 1
    Sounds like a bug... Mar 20, 2014 at 19:43
  • After upgrading to 10.9.2 this no longer seems necessary. I'm not getting any more "unable to create socket" errors in my logs. I guess Apple fixed this in one of their updates.
    – er0k
    Mar 21, 2014 at 16:41
  • Hehe! Called it! Jun 18, 2014 at 21:27

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.