I just picked up a Stiletto Ace combo and was checking the bias with my Weber Bias Rite meter. In doing this I found that the amp bias changed when switching the channels. It was biased colder when on the clean channel than the dirty. With the stock Mesa tubes I was getting 24ma per tube on the clean channel and 34ma on the dirty. Anyone else experience this? I wonder if they are switching the bias resistor via relay when the channels change?