As mentioned above, there is an issue with transferring larger files with 2.02
I just migrated my iTunes library to the NAS, and every song transferred fine, but these files (~300-600MB) copied as 0kb, thus the size mismatch.
Watching these files transfer, the file sizes grew, then went to 0kb upon completion.
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As an update, the 2.03 firmware beta on the spanish site did not fix this issue. Journalling seems fine, as FTP uploading does not have this issue. It must be in the SAMBA application.