Freezing clips during playback and export

In the last week, 2 of our office PCs have started to experience this issue. The files worked fine for the first 2-3 days of working on these video files, however, in the last 48 hours, both videos and programs have started to experience freeze frames throughout the video. So, if I grab the playhead and scrub through manually, and at a snails pace, the video seems to play without issue. When I play the video without rendering the timeline, it freezes. We thought maybe our network was having trouble suddenly, but upon output, they both had freezing in the output files. Has anyone experienced something similar? Any ideas as to what may be causing this all of a sudden?  

We have restarted our entire network, checked for software updates to the PC, Premiere Pro and NVIDIA. All are updated and current. I have tried some of the usual tricks like saving a new file and renaming timelines, pre-composing the entire timeline, restarts and rendering to MOV instead of H.264 with no luck. I know there have been updates to the Premiere as of late so I thought I would see if other users have been having these difficulties as well. 

Thanks!