Florian,
Thanks for posting the link to the sound clip. My 1-188-1 generates no clear repeats like those in the mp3. In fact it generates no repeats atall, even with Delay Clock set to zero. I don't hear the clock noise and aliasing at this setting either. If I turn the feedback up, all I get is hum. If there is a potentiometer i could try adjusting on the circuit board, I would try that. However I think the unit will need to be returned to Schneidersladen.
Cheers,
Blair