Rekordbox stuttering / not playing

Hi there,

Rekordbox is increasingly stuttering / pausing / tracks playing ultra slow.  It previously happened very very rarely, however is increasing in frequence.  

I've noticed that if recording at the same time, the recording will also pause, as the timer doesn't change during this stutter

During the stutter i checked Task Manager, CPU is sitting around 15%, and RAM at 70% usage (RB being the biggest user).  During any other time when non stuttering, usage of CPU and RAM is about the same

i am running latest version of RB (updated today), system is i5 2.4ghz, 8GB Ram, Windows 10, tracks are located on Onedrive, however they are saved locally on C:, which has approx 200GB spare

I am using DDJ-SX

Thank you!