An issue that I have since Mavericks/m466:
MacMini - Current Model
SSD drive for content
HDD for System
Clips will play fine and then at about every 30 seconds they will freeze for a frame or two.
It is not at the loop point and it does not seem to be clip related. Several different clips have this happen.

When this happens, I notice that in the Stats window MVC spikes momentarily and then drops back down.

I did not see this on a previous MacMini with OSX 10.8 (same specs).