If you're not already familiar with Rsync, it's the method (or 'protocol' to be posh about it) that BackupAssist uses to send data off-site to locations such as NAS boxes or to other servers.
QNAP make a NAS device that's popular with our customers and this week I came across an issue with backing up via Rsync to it that I've seen before...
...cue helpful (hopefully) blog post!