A:Answer Hi Hurk,
Power reset the AV receiver, simply unplug the unit and wait 1-2 minutes then plug the device back in and power on. If that doesn't work, perform auto-calibration and try again. Here's the link on how to.
https://helpguide.sony.net/ha/strdh79/v1/en/contents/TP0001559209.html?search=calibration
Happy to help,
David