The peak knob has a large effect on what the cutoff knob does. It emphasizes certain frequencies and creates a "peak" at these frequencies. If the peak is turned all the way up, the emphasis can be strong enough to increase the loudness of the sound and in some cases create an oscillation.
How To Make It
Start with this circuit: Power + Random + Filter + Delay + Speaker
Put the random module on "noise" mode.
Turn the time up (clockwise) on the delay module.
Turn the feedback up (clockwise) on the delay module.