the files change tempo (become slower or faster) when I drag them into the magix music maker 17. when i try to correct it using the fx rack the sound is in the right tempo but convulsive.
Plus, when you are in "adaptive mode" (which I recommend) any soundpool object you import will automatically be adapted to the arrangement tempo, which is 120 BPM as a default.
I highly recommend making your first track a simple Beatbox track and then adjust the tempo to the speed you want . (You can always mute it or delete it later.) That will lock the arrangement tempo. And THEN, add other soundpool objects, which will automatically be adapted to the tempo YOU selected.
You have heard the results of having the tempo of an object changed automatically and then you doing it once again. It is not pretty.