Volume pedal quack

[Nico Hillary]

Hi all,
Greetings from France! I have tried a number of volume pedals - an El Cheapo™ with upgraded 500k pot, a no-name active pedal, a Digitech multi FX with built-in VP, and finally a Korean Fender 60s reissue (model 726 ?).
Doesn't seem to matter which one I use, there's this weird duck fart 'quack' at the start of the travel, almost like a wah pedal. I've tried different amps, different guitars - Fender, Sierra.
Maybe I'm just hearing things. Has anybody else had the same thing, and is there an easy fix (without dropping 200 bucks on a Hilton)?
As always, your wisdom is hugely appreciated!
Nico

[Larry Dering]

I've used Goodrich passive volume pedals for 35 plus years and never heard the quack, nor have i on other players live. I also have used Ernie Ball, Morley and Dunlop without the quack. Goodrich are the smoothest passive pedal for me and thousands of others for years.

[Donny Hinson]

Nico, are you using any EFX in the volume pedal chain?