My mining rig is unstable (not software related I think), but I can't figure out why it is freezing.

Hi everyone,
I have a 6x RX570 miner and for all I know it is cursed.
Here is a pic to begin with: http://i.imgur.com/C7FUN67.jpg
The problem is that the miner keeps freezing whenever I move very rigorously around it. So my initial thought was that there is some loose connector, maybe power connectors or the risers. I jiggled everything and made sure they are firmly seated in whatever socket they belong. That didn't help. I also zip-tied all risers to the cards in case maybe one got loose over time, also didn't help.
Also I did lift the whole rig and started shaking it, but the miner remained working as if nothing happened to it. So I don't think it's any loose connectors and broken cables
But the moment I quickly walk away from it, it freezes. When I walk slowly away from it, it keeps working and if don't enter the room, it will work all day. However, I don't really have much space so someone is about to walk past the miner most of the time.
I was wondering if anyone else might have an idea what I could try to isolate the problem.