This works fine for me in Vegas Pro 9.0. Perhaps it’s the render template that you are using. Try a different one. Also try adding the pitch shift at the track level and see if that works. If it does, I would think something is going wrong in the render.
BTW, there are 100 cents in a semitone. So semitone = 3 Cents = 100 is really the same as semitone = 4. You might try semitone 4 instead and see if it makes a difference but it’s probably the render template.
~jr
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