Yes, CoolEdit was the first program I tried to do timestretching whilst preserving pitch, from what I can tell it does it by breaking up the audio into small pieces and overlaps them, certain notes 'warble' due to the frequency of the overlapping pieces. It's not something you immediately notice but once you do the music is ruined, my first try doing pitch preservation was on a Blade Runner LD rip, ruining Vangelis' music in this way is a no no in my books.