Have you considered decreasing your gear? In doing so you would decrease the torque applied to the cranks. At this point after your history that seems like the best choice IMO. For reference I'm an "A" track racer locally and race a 51/15 in mass start events. But I like to spin high rpms.
A few questions:
Were the cranksets new, or used?
What are the makes/models of the cranks used? I've personally had bad experiences with FSA cranks.
What are the lengths of the crank arms?
Have you been using the same frame this whole time? There may be something wrong with the frame.
Cheers,
Tmonk, a forum moderator
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