Lucia output is muted when using RS232 control
This could potentially be the RS232 volume settings, which is the reason that Lucia output is muted when RS232 control is enabled.
Send setvolume command via RS232
setvolume [output channels 1 to 4] [level -100 to 0 dB] <CR>
e.g. setvolume 1,2 0
If your issue persists, contact CareENTE@Music-Group.com with a detailed description of your issue and setup.