Well, it shouldn't work like that with properly designed amplifiers(and the higher gain amplifier is the one that requires less voltage input, anyway). Typical amplifiers have an input impedance of 10K ohms or more. Preouts typically have an output impedance of a few hundred ohms. A common rule of thumb is that the input impedance of the amplifier should be at least ten times the output impedance of the preamplifier. When Mojo and I discussed a similar problem a little over a year ago both on the board and in PMs the results he was getting indicated an extraordinarily low input impedance in the Axiom switching amplifiers was causing a drop in voltage when the EP600 was connected. The question was never resolved.
