Can't help you there except to say "it's audio". I've done a lot of audio editing using Adobe Audition and it has a highly regarded pitch change or time stretch algo in it and it's not as good as the one PG uses. A lot of people with more experience with this than me have commented on that. You didn't say if you have the pristine Audiophile version of the RT's. Maybe that helps. Most of us use the WMA's and those are compressed.
Just do a google search on audio time stretching and you can find plenty of technical articles about this. It's very tricky and difficult. You'll see that 5, 10 maybe 15% is about it and again it really depends on what frequency range it is. In Audition, I remember one file that I was trying to append to another file only required something like a 3% stretch and it still sounded glitchy. 3% for a 110 bpm file is usually no problem but I couldn't make it work. The track included drum cymbals and it was the high freq's that were glitching.
Someone commented in another thread that Melodyne has a superior way of doing this and maybe PG could adapt that but obviously, Melodyne would charge for the licensing if they choose to make it available at all. That's strictly a business decision, who know's what PG's thinking is on that.

Bob

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