Ears popping is caused by a restriction in the eustation tube running between your ears and your throat. It will swell when you get a cold and cause a blockage, the effects of which can be considerable. I have flown pressurised aircraft for years and have never needed to go sick with blocked ears. I suspect that the tubes have been exercised by regular exposure to differeing pressure and as such are maybe more flexible.
Taking an anti-inflamatory tablet (i.e nurofen) say 1 hour before flying (or descending) may well help alleviate the problem. If you are a professional pilot you should't really fly if you need to take medication to control a symptom.
I always consider how i would be if I experienced an explosive decompression. I believe that incapacitation would be the result of blocked ears.