@SUDCCIV – Zooms order for a lot of things is often hard to figure out!
Things like gallery view videos and participant lists entries seem to move sound a lot.
The presence of Host, Co-Host, Raised Hands (and other “feedback”) can affect position, as well as Spotlighting and Pinning videos. And if you are hiding people whose cameras are off (“Hide users with no video”), then people turnung on and off their cameras will affect the order.
Zoom does move things sound quickly at times. There are some ways to help control this: