Out of curiosity do you get this error in event viewer under admin events while playing apex? "Session "dfa2c640-651d-488d-a479-2fd7a7ca6e29" failed to start with the following error: 0xC0000022"
It's the only thing of note I noticed while playing Apex but it didn't happen every time the spike happened so I assume they are unrelated.
Had 4 games today with the first 2 games had no issues then 30 seconds after the first stutter happened I noticed that error pop up.Wierdly when the spike happened again 2 times later the error didn't pop up. (Always the same pattern frametimespike need I remind you.)