Sample Rate Conversion should NOT affect the Pitch of the Music.

The only time a Pitch problem will occur is when you originally recorded the Audio. Example:

You are Digitally recording from a DAT that is @44.1k but your PT Session is @ 48k.It sounds right comming in ,but later there is a pitch problem.

ProTools will "Convert after Bounce" the Data fine with "Bounce to Disk" if the Audio was originaly recorded correctly.

You MUST Make sure you are setting your "Sync Mode" correctly.This is found under "Setups" in ProTools.Go to the "Hardware" selection.Here you will see the "Sync Mode". If you are recording digitally from a DAT etc..the Sync Mode must be S/PDIF or Optical etc..If you are recording via the Analog inputs then you MUST use "Internal".Also your Sample Rate Selection here MUST match the source material.

VERY IMPORTANT!!!!

Make sure that you have the Sound Manager Control Panel "Sound" set so that its output selection is "Built IN" NOT "Digidesign" The Digidesign selection can cause clocking and playback issues.