| I think it's easy but often misleading to draw general conclusions from brake setups that are not performing properly for one reason or another. For instance, I know a number of people who run EBC HH (a sintered pad) with the brembo cast iron floating rotors with very pleasing result. That is not to say that you can have problems with that combo. Maybe organic pads are the recommendation. If you were to change pads and the problem goes away, it would be easy to say that Ferodo sintered pads are no good with cast rotors. But clearly some people have success with that combo.
I would try to figure what it is first. Are your rotors badly scored? Are they slightly warped? Maybe the pads have glazed over (my guess) and need removing roughing up with course sanding paper. I would definitely give that a try unless your rotors are warped or badly scored, in which case they need replacing.
Brakes are a funny thing. | 
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