Hi Kevin!
What about Ubuntu Studio? From what I've heard they're quite good when it
comes to audio and as they are related to Ubuntu/Debian their general package
base should be huge.
I don't know about PLF, but I've successfully used mplayer/mencoder and
other small utilities to convert proprietary formats into open formats. I'm
not sure about official mplayer packages, but I'm sure there should be some
packages. I always compile it from source.
I hope this helps, although not realted to your first choices.
Kindest regards
Julien
--------
Music was my first love and it will be my last (John Miles)
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