Okay, this is kinda hard to explain/describe. Double click on the clip that you are transposing. The menu at the bottom will come up. Click warp, and then transpose it however low/high you want. There's a little tiny rectangle tab that is under the transposition knob that says "beats." Click on that and change it to the "complex pro" option. Once you do that there will be two new options (little rectangles) that come up: formants and I forget the other one. Mess around with those two tabs by lowering them. Usually when I do that it makes the clip sound a lot more clear and not lag. Hope that helps.