Another Question about Z3TA+1

Hi there,
@first thanks for your replys in my other post there where very helpfull.
Know i got another question.
So i want to modulate a filter cutoff with a random lfo. The offset of the lfo is set at the highest with the aim that the lowest modulationpoint off the Filter cutoff is the point i've set in the filter section.
So if i set the range very high, the random lfo modulates under the cutoff frequency point i've set. With other waveforms there is no problem but with the random it doesn't work.
Is there a chance to achieve it with the ZTA+1 or basicly cant't the synth do that with random lfo's?
 
Very thanks and greetings from TA