A flac file is encoded with an unknown flac encoder. It verifies without integrity errors
in foobar2000. When it gets re-encoded with the official x32 1.3.2 build (same results with
2018/11 x64 1.3.2 build from rarewares.org as well), about 20% larger file size is produced. This
extent of the difference implies that a bug exists in the reference encoder that prevents
efficient encoding in cases like this one. The file is here http://kyriak.csd.auth.gr/track.flac
I can no longer download the track, but this might be fixed with https://github.com/xiph/flac/pull/245