Ghost files eating up hard drive space

I just bought a PR2100 and so far I’m loving it. I have a question regarding files that appear under the “other” category.

Before you say “these are system files” or “these are files that are not videos of music” let me explain to you everything I’ve done:

  • Only bay 1 has a 6TB WD Red hard drive and I formatted it using JBOD unspanned.
  • After initial boot up I updated to the latest firmware and installed Plex.
  • I created three shares
  • I uploaded in share 1, as a test, 42MB worth of random non-video files.
  • I noticed that the “Other” category was already around 2GB but I thought these were “system files” so I paid no attention but kept an eye on it.
  • Next I created a USB to NAS backup job and uploaded 1.3TB worth of video files. This backup includes only MP4 files, nothing else, as it is my Plex library.
  • After the backup finished, in the dashboard, the video category was showing 1.3TB as expected. But the “Other” category skyrocketed to 14.07GB for no reason.
  • I inspected all three shares individually and they all show correct values, 42MB, 1.3TB and 10KB

I’d really appreciate it if you can help me identify what could be eating so much space out of nowhere?

Thanks.

Here, you need to manually track and check the data stored in “Others” category and then erase inappropriate or unnecessary data. My Cloud does not take a backup of system generated or library files of OS.