If I use the transpose in obsidian, the sample change the speed. If Up fast and down slow. How can I keep the same speed in transpose?
Time stretch / pitch shift is not one of NS’s features. You need to use another app for that.
For loops you can try dendy’s hack https://blipinteractive.co.uk/community/index.php?p=/discussion/355/little-trick-for-timestretched-drumloop