Hull cavitation (shimmy) issues between small and large ships.

This is mostly for my son. I noticed that very small ships will wobble a little when near a very large ship, but for me this is rarely an issue other than to shake my head and frown a little. Oddly, though, my son's small craft wobbled so violently that it began spinning out of control, preventing him from working on it in build-mode (since, once you press CTRL, the ship flies off like a fidget spinner on crack). I have never had that level of shimmy, so I'm wondering if anyone has had this issue before, and does it relate to settings somewhere? Any help would be great. Thank you.

I loaded the largest ship I could find on my catalog to test the effect with the just a core and a couple of blocks. It does manifest on my game, but very slightly. It's like a gravity well of sorts forms around the larger ship. I can't recreate the crazy gyrations my son gets but we tested several different things. It's definitely based on mass or number of blocks, because sticking a 50^3 block of basic armor stopped the shimmy. I think the capital ship he's building is about 200k mass and a million or so blocks (it's on his private server). I can't help but think it's settings issue magnifying the minor effects I get, because the most that happens with me is a constant shiver of sorts, and that is at the most extreme end of things.

EDIT: Fays -- hey bud. We were typing at the same time, so I didn't see your answer. Nate (my son) was not tabbing between windows and his spinning ship was not in a fleet. The big ships were docked at a station. We exited and restarted StarMade and the spinning started again as soon as we turned the little ship to face the big one. Turning it away reduced the effects down to a shiver. Unfortunately, he was trying to dock the ship on the station to better work on his little ship.