recoding AUDIO only in videos (large directory)
 

What are the best programs for recoding just the audio in my movies directory? I have a ton of videos with DTS tracks which I use the popcorn MKV audioConverter for but I'm wanting to downsample the audio tracks to like my whole TV collection to save space since honestly I don't need super high quality audio while watching my name is earl, the jokes are still funny in 128K ;)