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[Dion Mraz]

[Baldrick]

What kind of audio? ac3, mp2,wav?

You could demultiplex the audio from the mpg using batchdemux and then normalize / boost the audio , if ac3 use http://forum.videohelp.com/topic317891.html , and then multiplex the new audio back to the mpg using imagompegmuxer.

Or maybe womble mpeg video wizard or mpeg-vcr has a normalize function...

[ytrouble]

its most likely the AC3 codec, download it, its free and try again