Fifth Gear T-Shirt Overdrive 'Heat' changes the DC bias

'Heat' changes the DC bias which causes static to be heard

The 'Bias' knob will starve the circuit fully off

Their info below

this pedal provides a versatile fuzz that can go from velcro-ey to saturated and everywhere in between

Overdrive on the right side

Fifth Gear T-Shirt Overdrive 'Heat' changes the DC biasGreat tones and muscle cars in one slick shirt. All our shirts are made and shipped by a third party. From their description: Enjoy everything you love about the fit, feel and durability of a vintage t shirt, in a brand new version. Slight scoop neck. Polyester retains shape and elasticity; Cotton lends both comfort and durability; addition of Rayon makes for a unique texture and drapes against the body for a slimming look. Slim fit Slight scoop neck