www.makemkv.com

This seems to be an issue with any Looney Tunes blu ray title. Various audio tracks can be duplicated up to 11 times. I'm basically using mkvextract to split out each audio track to a separate file and then perform a binary comparison of each file. If files are identical then I use MKVToolNix to delete the duplicate tracks.

Ideally makemkv could use metadata information on the disc to determine duplicates, or worse case compute some kind of checksum on the tracks as they're written out to see what turned out the same. These titles are always smaller than 2 GB (and less than 10 minutes), so that'd be one way to eliminate overhead in the common case.

I did a scan of TV episodes and found a few from the 1960s Bat Man series that had duplicated audio. I also found another series (Parks & Recreation ) where a few of the seasons (2 and 3) almost all episodes had duplicated audio that was wasting 800 MB per episode.

Something I'll have to deal with separately is The Twilight Zone--each episode has several tracks that aren't duplicates but do use uncompressed PCM audio.