Hi :-)

Here's an example soundfile: http://footils.org/snd/23.wav

With loopstart for example at sample 2912 and loopend at 5402, this looks
pretty even in the array overlay, but if you listen to it, you can still hear a
nasty rumble. I wonder, how to get rid of this ...

I thing this is due to the loop's frequency? With transposition 0 you get about 17-18 Hz. As you transpose lower it should sound smoother but at higher rates the loop frequency is heard as a pitched sound.
The problem is that a crossfade wouldn't really help here and I don't know any other solution (maybe filtering, but.....).

alabala

--
ypatios