Just like the NW-HD # Volume Limiter hacks used to defeat the European output limitation, there is a service mode trick that will do the same for the NW-A3000 and NW-A1000 as well. No word yet on the NW-A608, but it will most likely not be able to be changed.
Thank you very much to nw_lover for the tip.
For instructions, please read this thread: http://www.atraclife.com/forums/index.php?showtopic=509