As gravity and electromagnetism don't particularly jive, metallic objects that are caught in a magnetic field tend to feel the effects of gravity, too. Over time, the tweeters in the Paradigm 9seMk3's apparently leak. In the case of the ones I purchased used, it seemed to be a gradual thing. The bottom section of one tweeter was visibly soaked in ferrofluid.
I called Paradigm because I'd rather replace than repair. They said "They're just shot. How old are they? Just buy new speakers." They also claimed to have replacement diaphragms that they won't sell. Bummer. I understand their point of view. It was a mid-range product two decades ago. Why keep anything around for them now? Oh well.
I took the unit out of the cabinet and carefully removed the magnet and diaphragm assemblies from the front housing. I then lifted the diaphragm free to reveal that it a small amount of ferrofluid was leaking out of the unit, and had accumulated between the diaphragm and the magnet assembly. I then carefully used a q-tip and rubbing alcohol to clean the fluid off of the magnet.
Now what to do about the diaphragm? I took the same approach, only with minimal pressure and extreme caution. I put a small amount of alcohol on a q tip and began to rub the silk dome with alcohol. I did this front and back probably a total of a dozen times. Then i repeated the process with water. I blotted it dry very slowly and carefully with q tips. I was also careful to remove minimal ferrofluid from the coil portion of the diaphragm.
Assembly is the opposite of disassembly.
I reinstalled the tweeter, and did an A/B mono comparison using only the high frequency channel. I couldn't tell a difference beforehand in the two, and I still can't. Now the tweeter diaphragm is sans ferrofluid contamination. Mission accomplished.