Highly doubt you will get a free exam especially considering that you don't want to cancel your score.
Your complaint helps ensure that future test takers won't have to deal with that.
I also just took the december lsat in staten island and I couldn't believe how distracting all the noises were! The heaters were banging for an entire LR section and the proctors cellphone rang twice :( I'll be sending a complaint today...
If I were you I would be studying with no music in a public place. Like a library that is sort of busy. This will get you used to tuning out randomized outside noise.
@"Paul Caint" good idea on the neutral noise! I don't like studying anywhere too quiet because it's certainly not what test conditions will be like either.