“The Fuze will operate “solo” with a Griffin dock connected to a USB power adaptor. Will Rockbox allow the standard line out when dosked (not connected to a PC USB port, and no Data on USB pins 2+3)?”
Unfortunately no - I installed Rockbox on it yesterday, and as soon as I connected it to my Griffin Dock (powered USB Cable), the Fuze rebooted to official firmware. Which is a shame.
For now, I’m using official firmware on the dock - and rockbox otherwise (which is practically never).