TLDR, it was the Say Intentions VR toolbar panel.

This is a public FYI. Noticable in PMDG planes (heavy CPU load), in VR using Virtual Desktop, every 30 seconds (like clockwork) there is a roughly 1 second freeze...no new frames sent to VR, and image freeze in the headset. I've been troubleshooting this all week...drivers, Navigraph addins, background apps, etc.

I found the culprit today. It was the SI VR toolbar panel addin. The one that gives us the window in VR with frequencies, etc.

Off....smooth as butter. On, pauses every 30 seconds, I timed it. Repeated this over and over. The pauses are very evident looking at a chart of GPU load....drops to near 0 during the pause, as the GPU gets no new frames to render. I submitted a ticket to SI, but for anyone else battling this, try stopping the SI VR window, until a remedy arrives if the pauses are driving you mad.

Evidently the browser Asobo uses for VR toolbar panels is very old. I've seen VR panels load up the sim so bad it stutters (navigraph addin panel startup, GTN750 startup, etc.)

Folks have assured me that it must be something else in my system. I had tried everything else, from a bios update, Buying Process Lasso to move threads, stopping services I don't really need while gaming, clearing caches, shaders, updated nvidia drivers, you name it. According to SI, I'm the only guy on the planet with this issue. Maybe aliens have a cosmic ray generator pointed at my house.

In any case, just sharing this so someone might stumble across it when searching for bad stutter/pause every 30 seconds.

4 hours ago, BufordTX said:

It was the SI VR toolbar panel addin

I myself don't have SI, but I appreciate your analysis, efforts and feedback to the community!

When you close that SI VR window, does SI still work? In other words, what is it for, is this perhaps some sort of copy protection, license check or can you still use SI with this window closed?

The SI toolbar is just so you can see the panel in VR. You don't need it, as everything can be done with voice.