Yamaha Aventage RX-A8A User Manual page 371

TROUBLESHOOTING > When any problem appears
Any other device's audio is played back when you switch the input
source of the unit to "TV"
(
The eARC/ARC function is not used.
Audio is played back with the audio input jack selected in "TV Audio Input" in the "Setup" menu unless
the TV audio is played back with eARC/ARC function. It is not a malfunction.
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