SC,
The cabin pressure in an airliner only descends at a maximum of 500 feet per minute. In fact 300 feet per minute is normal. The aircraft descends faster, but the cabin does not.
If you have a blocked ear in the cruise then sort it out before the aircraft descends. As it descends the pressure builds up in your ear and it becomes harder to clear. Suck a mint sweet (cabin crew will have them for young children, but they are good for big kids as well). Hold your nose and blow. This can cause dizziness and should be done carefully in conjunction with the mint sweet sucking.
If you have a known problem before you fly then take some medication with you such as Mucron and / or Sinex to clear your nose, etc. Take it about 20 minutes before the aircraft starts it's descent. For passengers: the descent will start about 25 to 30 minutes before landing time (listen to the pilots PA for that).