[AAR.oner]

you'd need to demux the vob files into video & audio streams, then import the audio stream into yer audio production prog to adjust the pitch...then import the corrected audio back into a DVD authoring prog to mux/create dvd menu/etc

i usually use ffmpegx or MPEGStreamclip to demux, and then Ableton Live or Logic for audio post work


honestly tho, its a LOT more work than you'd think...unless yer an audio engineer and have the knowledge/gear to do it, i wouldn't waste my time...just my .02