I noticed this started after I bought a new power conditioner (Panamax M5100-PM). I turn off the Panamax when my electronics are not in use, and the receiver is NOT plugged into the "always on" outlet. Could this be the problem?
That's a Big 10-4 Good Buddy!
When you turn OFF the Pioneer it is not really completely OFF but in a "Standby" state with power still being supplied to your Pioneer.
So, When you turn off your Panamax and your Pioneer is not plugged into "Outlet Bank # 1" (always ON) it is essentially unplugging your Pioneer and it is no longer in a Standby Status.
Go to Page 25 in the OP Manual and it tells you that each time the Pioneer is plugged in (turning ON your Panamax) the Pioneer will go through a 2 to 10 second HDMI Initialization process
and you cannot carry out any operations during this process!
You are your own "Worst Enemy" and making your Pioneer constantly go through this process over and over again!Your Pioneer should be plugged into "Outlet Bank 1" "Always ON" on the back of your Panamax!
Your Panamax will keep your Pioneer Safe & Happy!
Once your Pioneer is constantly powered up and in it's necessary "Stand By" State, ALL will be Fine!