I've had two issues occuring since the first of the year that is effecting BF4.
#1. I see CPU usage climb to 99% with FPS dropping in the red to usually 15 FPS. Last about 19 seconds about once a game.Could occur anytime whinle in game so I dont think it's punkbuster.
#2. Game crashing to desktop. No error message. Usually I see the action stop for 5 seconds then it goes to the Origen whidow. If you hit ALT F4 that is sudden, but this looks different. Sometimes I see "Lost Connection".