I’m not able to configure LCR to work properly. I’ve selected it from the menu and then applied but only the C channel receive and output signals.
The LR does not receive anything.
What can I do?
try again 
not funny
more information would be helpful…
pan in the middle should lead to no signal on L/R only in C
LCR is a ‘hard pan’ mode, from L only through to C only and R only as you adjust the control.
For an LCR+ approach to mixing (with a ‘blend’ control to adjust the amount of C vs LR) try 5.1 mode, where you can select LR, LCR or LCR+ independently for every channel, and use the Divergence control to blend C vs LR. Just discard the surround channels if they are not of any use.
Thanks, I was totally ignorant about the LCR mixing mode. You both have solved my question. Thanks again.