Multi­zone Function; There Is No Zone Output From The Connected Player - Onkyo TX-NR545 Manual

Troubleshooting
Multi­zone Function
There is no zone output from the connected player
With multi­zone function, sound is output only when the signal input
source is an external component connected to the analog audio input
jacks, "NET", "BLUETOOTH", "AM" or "FM". Multi­zone output is not
possible if the player and the unit are connected via HDMI cable.
Connect the player using RCA cable. Also, some players require audio
output setting.
Only analog audio signals can be output from an external component to
Zone 2.
When the "NET" input source is selected, DSD and Dolby TrueHD audio
signals cannot be output to Zone 2.