> Does anyone know how I could increase the volume
> of a particular audio file? It recorded very softly ...

Recording it softly and then bumping up the volume level is roughly
analogous to shooting a picture at 640 x 480 and then blowing it up to
an 8 by 10.  You may get a servicable picture, but can never recapture
the lost resolution.

It is far better to re-record (if possible) and use every bit of every
byte you've got (and no more).  If the softs are too soft, and the louds
too loud, consider an audio compressor to reduce the dynamic range of
your source.  I only know the hardware kind (plentiful and cheap on
e-bay) although I'm told there are software audio compressors too...

Those are my two bits.  Perhaps you already knew all that.  In which
case I apologize.  

Can I ask the group -- is there good audio software out there for
Linux?  You know -- VU meters, mixer, editor, perhaps a synth channel or
two?  My son is a FruityLoops fanatic (he does recreations of game music
on MP3.com -- artistname "kikuichimoji").  Anything synth-like in the
linux world?  I know, I know -- Google.  But anybody out there into this
kind of stuff?