I'm having problems when using 2 amps, example,, a vox and a treadpalte, when I turn on the treadpalte the sound clean vox leaks in treadplate, the only way to solve it was giving vox mute the channel, but that  turn off volume  the vox , what am I doing wrong? In mixer if I give a mutein the channel of vox  solves the probema but I believe that should  another solution