LFO ticking in PT2399 'Optowobbler'

[Ksander]

Regarding the input impedance of the PT2399, I thought the signal enters the chip through an inverting op amp? Either way, I tried adding a 1M resistor to ground at the input (as I understood, this increases the impedance?). This did not appear to affect the sound.

[antonis]

I tried adding a 1M resistor to ground at the input (as I understood, this increases the impedance?).

Actually, it makes things worse 'cause it's set in parallel with whatever is the input impedance..

[Ksander]

I see, so instead I'd increase R1 and R32 and decrease C24 each by a factor 10 for instance? What about C21?