I had some stuttering yesterday, on approach to LEPA in a CRJ 550, with multiplayer on and a fair few players in the vicinity.
I had also had some rather odd experiences during the flight from LFLL, including a co-pilot appearing when i was in the cockpit and the animation of the throttle and other controls stopping.
The stuttering only seemed to occur in VR.
I put it down to one of the modules in my Community folder and so repeated the flight, having emptied out everything but the CRJ and the Navigraph data. I had no repeat of the issues when i arrived at LEPA. However, the fact that the LEPA area was a lot quieter made me wonder whether multiplayer might still have somehow played a role in the stuttering.
I therefore did a search of the forum and found this thread, which might be connected with what the OP, and others, are experiencing.