Additive VCO with Arduino (Hagiwo)

I have a liitle problem with this build.

All works fine except when i plug a CV source in 1V/oct input jack.

there some little “clic” or “cric” on the sound (and for an ambiant module sound is not good at all :unamused:)

I tried differents CV source but allways the same “clic”

an idea someone ?

i precise that mine is build with a TL071