Muse Model Two DAC: converting from 1 volt output > 2 volt?

Does anyone know how to convert the output voltage of the Muse Model Two DAC from 1 volt output level to 2 volts?  Inside the until there's a little check mark on the two options, but with (I think?) Kevin no longer among the living - does anyone know how to make this change?  The original sales literature for it also show this as a factory option. 

Is it a simple DIP switch somewhere inside that doesn't require unsoldering/soldering?  It would mate with my preamp / amp a lot better with a little higher output.  

Thanks in advance!
Mark