@gbooker02 I went through past PMS versions, and the last version where ViewStateSync worked was 1.40.5.8854-f36c552fd.
I also confirmed that the exception started happening on 1.40.5.8897-e5987a19d: Plex Media Server - #638 by gbooker02
Maybe something to do with
(View State Sync) Item plays could be duplicated when state synced from service.
(ViewStateSync) Fewer requests to plex.tv endpoints (PM-1958
