When I have ECO turned to "OFF" I never hear a clicking sound from the AVR because it does not change modes in "OFF". It's only when I set ECO to "AUTO" that I hear the AVR change gears between 47-50. Maybe our units are different in some way? Or maybe the load matters? I will study the eco meter and see what it shows. Thanks!
There is no chance of them being that different, because I have compared the schematics of the 4400 and 4500, and 6014, they are all the same.
As I mentioned before though, there is a time delay between switching on and off. It is far from instantaneous. You have to wait to hear the very quiet click or you will miss it. It is much easier to observe the onscreen display energy use bar, but then you still have to be patient as they display goes off after a few seconds so you have to keep pressing the volume up or down 1 notch just to keep it alive.
So to observe the switching, I suggest you set the volume to say -25, move the volume +/- 1 every couple seconds until the energy use bar shows Eco off, that is the bar would be about 1/3 or more full scale. Once there, then reduce volume to -30, and do the same and see if the energy bar would show Eco coming "on", that is showing less than 1/3 or somewhere around there from the fully bar when Eco was off. If not, increase volume to about -39 or lower and wait again, while moving volume between -38 to -40 just to keep the bar on. If you wait long enough, sometime may take a minute instead of seconds, but it will switch, promise..
That's just so you can see the click instead of hearing it. To hear it you have to do the same but have to be close the AVR to hear it unless you room is very quiet and your hearing is very good.
If you want to see for yourself Eco "auto" is same as Eco "off" at higher volume, all you have to do it to set the volume to say -23 again, and move the volume +/- 1 or 2, that is between -24 to -22 and you will see that it will never turn "on" even with nothing playing.