Interesting, I have two Macs backing up via Time Machine to a Synology (over ethernet) and both have regularly suffered corruptions where they have to restart the backup from scratch again. It's infuriating.

Were there any specific tweaks you made to your setup to make this reliable?

I also wonder if the amount of backup data makes a difference. I have tended to use Time Machine to backup pretty much my whole drive. I wonder if it's more reliable when backing up smaller amounts of data perhaps...