I have a Sunn 1200 head and Gallien Kruger 410 cabinet and when I first plug in sometimes there's a Pop! that sounds like a bomb going off. I'm actually surprised it hasn't imploded into an Event Horizon! I'm used to tube amps and I have grown to really love this amp, is the ohm setting wrong? I don't really expect an answer but the Sunn head is compatible with any cabinet, what is the problem?