Because most of my cabs never get truly finished I've a lot of loose wires in many cabs, and vibrating wires do happen but not often. I usually fix one end to the speaker itself with cable ties leaving enough slack to avoid stressing the connections but tight enough not to flap around. I bury the other end under any wadding and that stops that moving. I don't leave a lot of slack though, just enough to be able to remove the drive unit easily