I'm trying to re-encode a movie that is about 6GB down to 4GB, I want to keep the video bitrate the same, but knock down the audio from 5.1 to 2.0, and I went to use Handbrake to do this, but I wound up with a file than was larger (13GB) than what I started with? How did this happen? I can't use a program to enhance what already is there, right?