Connect realtek card to av receiver

[QVENGADOR]

Hello, I would like someone to tell me the reason why when I connect to my PC through an optical output to the AV receiver I can't hear it correctly. I only get sound through one speaker. And the rest has no effect on the home system.
A little help please

[Namiga]

What is the home effect?

[whoololon]

Either the connection is faulty somewhere or one of the devices (source or destination) is not configured correctly.
I join the mystery of the "home effect".