S3 backups fail

Ok this is a odd one.

If I do a manual S3 backup in the foreground it works. Socket doesn't time out at all.

If I do it in the background it fails every time.

Failed to create S3 bucket : Your socket connection to the server was not read from or written to within the timeout period. Idle connections will be closed.
Backup failed! See the progress output above for the reason why. Total backup time was 01 minutes, 32 seconds.

Now what would cause this to happen ?