This issue seems difficult to reproduce in a controlled environment, since it seems to depend on high network load. It's also not noticeable in many instances, because if a marker or silly prop doesn't have its position synced, nobody would notice.
However, we run a weekly event in Kaleidosky, which has very high capacity, very high idle bandwidth (tens of VRCObjectSync objects moving constantly in the lazy river), and critical object sync positioning. Since the skybox is based on camera feedback, unsynced objects can cause vastly different sky experiences for different users (occasionally as far as seizure inducing).
We've temporarily worked around this issue by causing all users to call FlagDiscontinuity() on every VRCObjectSync they own, 5 seconds after any new player joins. This seems to force vrc to resync the VRCObjectSync's position properly every time, but is definitely a big waste of bandwidth in an already choked world.