[LAU] Timestretch without sample damage.

The audacity time stretcher is great, rubberband is even better but they both put chunks of silence into the samples when I use them. So far the only way I've found of getting around this is to stretch it (or crush it) to close to what I want, then remove the tiny chunks of silence and then use a speed changer in audacity to make the sample exactly how long I want it, which of course affects the pitch but unnoticeably. Am I doing something wrong when using these tools? The problem I'm trying to solve is to get a chunk of wav of length y to be of length x without affecting pitch. Existing tempo changers that I've seen put some silence in the output file when I use them. Again, usual disclaimer: If I'm being stupid, let me know. God Bless Jonty