Same experience here too. Try to avoid Dwarka center.
I wrote my test in Jan 26, 2015 and it was election time in Delhi. As soon as my verbal section started, some extremely loud election processions started downstairs. I tried using one of those earplugs. I guess even calling them earplugs is a joke. They were just two plastic thingies that were of no help whatsoever. At one time, I just couldn't concentrate anymore, guessed the last 10 questions and came out of the center.
No wonder, this particular test center has a ton of available seats every time I look at it. Soundproofing is a very basic necessity for any test center. I guess, Pearson guys have made it a business (an unethical one) in this case.
Anybody thinking about taking test here, please don't go here.