I have a sony TV a Denon AVR-X2500H and a Sony X 800 DVD Player. For the life of me I cannot figure out how to play a CD on the DVD Player without the TV going on. Not sure if it is a wiring issue that I did wrong or a setting or what. Hopefully someone can help.
My guess is that this is caused by
HDMI-CEC (that has many marketing names
) and can be turned off/on or partly disabled (like power on/off and/or input switch which is probably what you want). Usually this is buried in some obscure setting in some menu at some arbitrary menu depth depending on the device, and likely to keep you occupied for some time
Those using an universal Harmony remote from Logitech should disable all power on/off as well as input switching. It really messes up the remote unless some parts are disabled, but I use it strictly for Chromecast play/pause/stop so only the TV and reciever has it enabled (with restrictions).
I've got an older 2015 model AVR-X4200W where I could disable power on/off, but this is for your model if in NA:
http://manuals.denon.com/AVRX2500H/NA/EN/GFNFSYkfayrqor.php
Your DVD player (Blue Ray, I assume?) has similar for disabling CEC, I think.