Mainstage 3 Loopback Query

Hey Guys,

I'm new to MainStage 3 and am mainly interested in using Loopback on it. I followed the tutorial and can start and use loopback on one channel just fine, but when I go to use it in another channel (to lay another loop on top) it immediately cuts out. What have I missed? Have turned Sync on and put both loopbacks in the same group. Anyone?

Thanks,

JD.