Zoom G3 and Vox VT30 help!

[paradox.]

Hey guys, just bought a zoom G3 and connected it to my vox vt30. I'm not sure if multiefx and the amp is not compatible at all. My vox amp effects even tho turned off or at the minimal level, the effects are still turned on while nothing is activated on the G3! Please help!! I've tried different settings but it still won't turn off, I'm on manual mode on the vox. Without the multi efx plugged in, the amp effects are off, but once plugged in its on without turning the amp effect knob. Please please help