Two more: "Removal of decoupling capacitor C3020" and "Route ROUT1/LOUT1 back to LINE1/LINE2 input". ECN0037 explained which voltage we don't want, but left the one we get as an exercise to the reader. I've added "With R4416 = 10k, the low level voltage is 0.55 V." (Hope that's correct :-) - Werner