Trying something new in addition to the syncs. I was syncing every 20 minutes, which left the skew small, but occasionally it popped up in small variances. I'm attempting to tune the frequency and tick kernel parameters to more closely sync kernel tick with actual time. It appears these were slightly off, creating the issue. The NTP could sync it, but it would get small variances between syncs.

Hopefully together they will solve the issue. Keep me informed if you notice again.
--J