Background Remote Backup fails

I have several remote backup jobs configured to backup data from one PR4100 on my network to another. All jobs run to successful completion when run manually. When left to run on their own they fail (code 1400), but again, as I log onto the source PR4100 and manually run the failed backup, it runs to completion. Why can I run it manually, but it fails automatically?

Hi @ChrisEM

Have you checked our knowledge base articles?
(Support for Western Digital Hard Drives | Western Digital)

Have you opened a Support Case?
If not, contact Western Digital Technical Support for assistance.
[Contact Us | Western Digital]