I had forgotten to reset the time on my SMP for DST. I reset DST, and the next time I powered up, I was missing 30% of my movies from the media manager. Finally had to delete the .wd_tv file and rebuild, then it was OK.
After thinkiing about it, this happened the last time I manually reset DST.
No one else has ever mentioned this that I’ve seen, so I guess it’s just me. Just FYI.