Particle balls occasionally need their covers refreshed with some type of resurfacing regardless of whatever 'bleeding' technique you decide to use. The pores can be fresh, but if the particles are worn down, reaction is going to continue to suffer.
My doubles partner declared his Super Carbide Bomb 'dead' a few weeks ago. He first bleed the cover using controlled oven heat in the Rejuvenator (Brunswick/Lane#1 recommended), but there was little improvement. I then took the ball home and did a light resurface with a 35 micron trizac pad, and the ball has come back to life.
Consider cleaning, bleeding and resurfacing together as a complete solution.
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