The newest firmware for the Noxon Audio player also supports FLAC...
It is available here: ftp://ftp.terratec.de/HomeEntertainment/NOXON2/Updates/
The firmware has to be installed with the Noxon Firmware Manager (if the webinterface of the Noxon is not yet capable - because of a too old version).
Under windows newer windows versions, the XP SP2 compatibility mode has to be used, otherwise the Firmware Manager won't find the Noxon!
Also both the host computer and noxon must be connected to the network, preferrably both using a lan cable, or both wireless.