How do you have HyperBackup setup? I want to use external USB drives (so I can store copies offsite) and from what I've read it won't span backups across multiple drives - my Synology capacity is 20TB and the external drives are 8TB. So what I'm doing now is doing old-school file copies across to a desktop machine, which isn't ideal.
I tend to not run many apps on the NAS but I do use HyperBackup for local and remote backups, and it works pretty well.