While doing some auditing of servers after reboot, I found that ntpd was not running and that system time was off.
$ /etc/init.d/ntpd status
ntpd is stopped
This meant that freeswitch's time was also likely to be incorrect. I verified by entering the following freeswitch command:
$ fs_cli -x strftime
After confirming that the system clock was out of sync, I executed the following commands in order to sync the system time with a known good pool, start ntpd with the corrected time, and then force freeswitch to sync with the updated system time:
$ sudo /sbin/ntpdate 0.north-america.pool.ntp.org
31 Aug 05:24:20 ntpdate: step time server 126.96.36.199 offset 25202.399733 sec
To start ntpd:
$ sudo /etc/init.d/ntpd start
Starting ntpd: [ OK ]
And finally, sync freeswitch with the corrected system time:
$ fs_cli -x 'fsctl sync_clock'
+OK clock synchronized
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