kevinturcotte said:
It does, but the only thing that seems to work is when I turn the Tv OFF. Volume control, and turning the Tv ON doesn't do ANYTHING to the A/V receiver.
Like I said, CEC can be frustrating. Try actually removing power (unplug) from both devices every time you "play" with the settings, replacing power to the TV first and waiting for any boot process to complete before reapplying power to the AVR. There are numerous layers of control for both power and volume. Unfortunately they are not "standardized" as to what they are called. Take some time with the manuals and look in avsforum.com for threads specific to your TV and/or receiver. You're in trial and error territory here but if you get it to work it's awesome!
I had numerous issues until I received a firmware update for my TV and all was well (in fact I think it what was wht YOU are seeing but volume control worked. TV was Vizio and I think they use LG glass for this model) See if you can find a firmware update. Also, I had an Onkyo with CEC and found their tech support to be very helpful. You may want to call, especially in the price range of your receiver

. Call LG too.
EDIT - Typically there is only one port in your selection of HDMI inputs on the TV that support all the feature and ARC. Look for one labeled ARC (Audio Return Channel) or try all ports. Jump to avsforum.com for this topic

Best of luck
EDIT 2 - On the Vizio I've got CEC on, System Audio control ON, and device discovery shows my AVR-891. On the Denon it is simply HDMI Control ON. You've made me remember why I no longer have the Onkyo 508. After going through 2 of them, could never get the CEC to fully work. Exchanged for the Denon 891 and and the power control worked, volume control only worked for the AVR, and then the TV firmware update fixed the volume control for the TV.