It seems like my WD TV Live stops loading the metadata after 2 minutes. Movies starting with A until D (not exact) have now metadata but then the process seems to stop and does not pick up again. I have restarted the metadata process more than once but always with the same result.
Yes, this is exactly the same problem as I am having. Due to a recent problem with my hdd all my library had to be rebuilt.
As a result all my metadata was gone.
No matter what I try I can only make it from A to D, same as you. I have tried clearing the metadata and doing a few things but same result everytime. Due to my circumstances I have no idea when this problem may have started.