Visible crew/equipment: When they spot the moon, Aeryn walks to the control systems and says "How could we miss it?" If you watch closely you can see the boom mic come in to picture above her.
Visible crew/equipment: After Crais asks if Aeryn have seen the surveillance logs, it cuts to a close-up shot of Crichton. If you look closely up in the left corner of the screen you can see the boom mike pop into view.
Chosen answer: It's never explained. John mentions a theory that his less technologically developed craft simply interferes with the wormhole less than the "superior" Vipers, but they never make a concrete determination on that point. But we also have to take into account the fact that Moya traverses wormholes with no ill effect as well.
Garlonuss ★