[pezdudenyc]

Hi Andy,
not to sound patronising or state the obvious, but when you have put in your required number did you hit the tab/enter key afterwards? Reason I ask is I made the same mistake a couple of time...entered the number on the semitone window and pressed process. nothing. because i didn't actually ENTER the darn number!
Use tab or enter. then also give the audio a second AFTER the process is over just to rebuild the waveform and you should hear it.
Hope that helps.
M