Is your server configured to prefer embedded metadata, or is it drawing from Last.FM or Gracenote?
I used to let Plex use the online services, but I had nothing but trouble with it. Since I reconfigured Plex for embedded metadata, and got my embedded tags in good shape, those troubles are gone. I can’t say that I’ve seen your particular issue (I’ve never bothered with rating tracks), but I just tried what you described and I can’t reproduce the same behavior. It works as you would expect. So I’m wondering if it has something to do with the metadata Plex has for your tracks, or a database corruption problem, or something else.
What are the versions of Plex server and Plex Web are you using? What OS is your server on?
