Switching between dry and synth signal on Quad Cortex with Midi Guitar 3 on ipad

For those using a Quad Cortex with midi guitar 3, I am trying to switch between the synth and dry signal using the actual switches on the Quad Cortex itself. I can achieve just the synth sound by soloing the USB signal but cannot get just the guitar signal with any of the solo or mute options available.
Thanks