Currently Being ModeratedFeb 25, 2013 7:47 AM (in response to cmautner)
Can you go back and turn the mp3 into an AIFF before you run it through Levelator? AIFF is GB's internal format, maybe that works better (although a .wav file should work and the quality should be the same.)
And if you can go all the way back, leave out the mp3 stage - that's an unnecessary compression and decompression step that degrades your audio quality. Export the audio at full quality from GB (which is an AIFF) and go straight to Levelator.