Reduce noise from Colorsound Wah-Fuzz-Swell?

[Superferry]

I have a Colorsound Wah Fuzz Swell pedal. It sounds awesome but it's noisier than hell when I stop playing (and the fuzz is still on). Even when I cut the signal to that effects chain (with fuzz still on) with an A/B switch, it's still noisy. Is this normal with this pedal or is there any maintenance that I can do? Hilo is pretty humid and relentless on gear, so maybe there's some corrosion somewhere? The Wah is also a bit noisy. Any suggestions? Thanks!