Make the attack time non zero? An attack time of zero is expected to click, at least on many hardware synths i own, just adjust the attack time slightly. does that solve your problem?
Think about it this way, a click is usually a very fast and abrupt change in the waveform, which is exactly what a fast attack is. Going from 0 to full volume in 1ms for example.
If i use a sine together with a low note, i need to increase the attack time a lot - some times i need more then 20 ms to avoid a click sound… I mostly set the random phase to 0 and tried different phase start - which doesn’t make any difference.
If I create a patch with this issue i will upload it.
Ok just checked it again it is more then 50 ms to avoid a click sound if i use a sine (basic shapes) - and hmm maybe i was wrong, if the phase is set to 0 it helps a little bit but still need around 50 ms to get no click sound. I played E1 (which is one octave about the lowest note on a bass) with 1/16 note length and 1/16 space between the notes.
Ok, it’s more complex then i thought - just played with the attack time - with 13 ms i also get no! clicks with 0-12 ms or 14 -19 ms i get clicks. At 20 ms almost no click, 21-25 ms clicks… and so on.
So i guess i will use the 13 ms. And still can sharp the attack with its curve.