I just got my Turris Omnia in the mail.
I noticed that it was rattling, so I had to void the warranty and open it up to investigate.
Turns out for two of the miniPCIe slot standoffs the screws on the bottom had gotten loose during transport and fallen off, with the screws on the bottom and the standoffs on the top of the board rolling around inside and rattling.
Maybe the washers used are too stiff?
Or the screws weren’t tightened enough during manufacture.
In any case the screws are back in now and I’m looking forward to trying it out. 
By judging this whole concept (it is more like dev board with routing and switching capabilities, than actual router), I don’t think you actually voided your warranty by opening the case… 
It is meant to be opened and tinkered with…
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