I have a similar,but different problem going on.
I just bought SAP Quartettes----Ever since, I've been thinking of some way to keep the tops from falling off. The bottom is the bass cabinet with cones/discs between. The first week or so, in just changing wires, I would have a cone-set topple.--I should mention I am blessed with 6 thumbs per hand. I know I have to keep the cones and was thinking: maybe 14 bricks on top of each speaker,might help.